Oryza sativa L.) contributes to the diets of around 3.5 billion people every day and is consumed more than any other plant. Alarmingly, climate predictions suggest that the frequency of severe drought and high-temperature events will increase, and this is set to threaten the global rice supply. In this review, we consider whether water or heat stresses in crops — especially rice — could be mitigated through alterations to stomata; minute pores on the plant epidermis that permit carbon acquisition and regulate water loss. In the short-term, water loss is controlled via alterations to the degree of stomatal “openness”, or, in the longer-term, by altering the number (or density) of stomata that form. A range of molecular components contribute to the regulation of stomatal density, including transcription factors, plasma membrane-associated proteins and intercellular and extracellular signaling molecules. Much of our existing knowledge relating to stomatal development comes from research conducted on the model plant, Arabidopsis thaliana. However, due to the importance of cereal crops to global food supply, studies on grass stomata have expanded in recent years, with molecular-level discoveries underscoring several divergent developmental and morphological features. Cultivation of rice is particularly water-intensive, and there is interest in developing varieties that require less water yet still maintain grain yields. This could be achieved by manipulating stomatal development; a crop with fewer stomata might be more conservative in its water use and therefore more capable of surviving periods of water stress. However, decreasing stomatal density might restrict the rate of CO2 uptake and reduce the extent of evaporative cooling, potentially leading to detrimental effects on yields. Thus, the extent to which crop yields in the future climate will be affected by increasing or decreasing stomatal density should be determined. Here, our current understanding of the regulation of stomatal development is summarised, focusing particularly on the genetic mechanisms that have recently been described for rice and other grasses. Application of this knowledge toward the creation of “climate-ready” rice is discussed, with attention drawn to the lesser-studied molecular elements whose contributions to the complexity of grass stomatal development must be understood to advance efforts.Rice ( Feeding a global population expected to reach 9.8 billion by 2050 is one of the greatest challenges of our time . TogetheOryza sativa L.) is a major source of food and income for billions worldwide. In Asia, where over 90% of rice is grown and consumed , with CO2 uptake for photosynthesis (A), evaporative cooling, and nutrient transfer often diminished as a result , and this is beginning to be translated into grass species (to name a few: Brachypodium distachyon), and other grass species of agricultural importance such as maize (Zea mays) and barley (Hordeum vulgare). Then, translating this knowledge into action, recent advances towards “climate-ready” rice with altered SD will be discussed.A deep understanding of the stomatal development program in rice is required for genetic manipulation of SD. The majority of our existing knowledge stems from the model plant Arabidopsis  are monocot grasses and, relative to eudicot plants such as Arabidopsis, are defined by a number of distinctive features relating to where and how stomata develop . In grasFor most plant species, including Arabidopsis and grasses, the stomatal lineage progresses in much the same way; originating from a set of undifferentiated epidermal cells at the base of the leaf known as protodermal cells . The stoThe divergent developmental processes described above during the beginning of the stomatal lineage are briefly realigned when meristemoids in Arabidopsis transition to GMCs and take on a form similar to that of grass GMCs Figure 1scrm scrm2 knockout plants fail to produce cells that enter the stomatal lineage  transcription factors are primarily responsible for regulating stomatal lineage entry and subsequent advancement to mature stomata. These bHLHs are known as SPEECHLESS (SPCH), its close paralogues MUTE and FAMA, and SCREAM  and SCRM2  Figure. MUTE ac lineage .There are many hormonal stimuli that directly and/or indirectly regulate stomatal development. For example, the abiotic stress signal abscisic acid (ABA), is known to be an important regulator of both stomatal development and stomatal closure . HoweverSPCH, MUTE, FAMA, SCRM, and SCRM2 are highly conserved across land plants, with SPCH undergoing a duplication event in grass species  mutants  and, in some cases, undivided SMC cells are detectable in osfama knockout plants , suggesting that the heterodimerisation of bHLH transcription factors observed in Arabidopsis also occurs in rice  have now been confirmed in vitro via bimolecular fluorescent complementation (BiFC) and yeast two-hybrid (Y2H) assays , Arabidopsis T-DNA knockdown plants with little-to-no SCRM expression produce a range of stomatal lineage cells (at various aborted stages) as well as stomata (osscrm T-DNA knockouts are examined in rice (which display a weaker phenotype than CRISPR osscrm plants), the function of OsSCRM appears to more closely mirror that of AtSCRM. This is because aborted stomatal lineage cells can be observed throughout the development stages, implying that, together with OsSPCH1/2 in early development, OsSCRM probably associates with OsMUTE and OsFAMA in vivo  assays . Like Ar species . Whereas stomata . However in vivo . In cont species .bdscrm and bdscrm2 single mutants produce a seedling lethal phenotype, owing to an inability to produce mature stomata  experiments identifying over 8,000 genomic binding sites . To coorArabidopsis uses apoplastic cysteine-rich signalling peptides called epidermal patterning factors (EPFs) and EPF-like (EPFL) peptides to convey extracellular signals between stomatal lineage cells, mesophyll cells, and cells destined to become pavement cells  Figure; EPF1 byEPF genes involved in negatively regulating stomatal development in grasses  is required to enable a more succinct understanding of how rice stomatal development unfolds.In barley and wheat, istemoid . Given t lineage . As withinstance . Clearlybdyda1 knockout mutants have a large increase in SD and a severe stomatal clustering phenotype, whereby approximately 86% of stomata are involved in cell clusters. Interestingly, rather than arising as a result of faulty physical asymmetry in cell divisions (as in Arabidopsis yda mutants), cell clusters in bdyda mutants result from a failure of differentiation and fate reinforcement after asymmetric entry divisions have already occurred , in the shoots to position bundle sheath cells around the developing vasculature ((i) vascular patterning and stomatal patterning are coordinated, (ii) stomatal cell files are specified  adjacent to procambial centres in grasses, and (iii) OsSHR1 and OsSCR1 are expressed in stomatal lineage cells, it was proposed that SHR-SCR interactions might contribute to the specification and spacing of stomatal cell files in grasses  does lead to the formation of extra stomatal cell files positioned further from the leaf veins  or whether OsSHR1 or OsSHR2 are genuinely incapable of promoting new stomatal files in rice.Until recently, the positional signals that prompt the specification of grass stomatal cell files remained unclear. Schuler et al.’s  study ofculature . Given t grasses . Indeed,af veins . In line lineage   and in cdkb1;1 mutants, and the nuclear DNA content of cells from the former is double that of normal GCs, suggesting that they are arrested at the G2-to-M phase  complexes are known to govern cell cycle transitions . In the -M phase .CYCA2 gene, OsCYCA2;1, is present in the rice genome . Direct examinations of whole-plant water use have shown that OsEPF1-overexpressing (OsEPF1oe) plants consume around 40% less water than control plants over equivalent periods, due primarily to reductions in sg  outperform both control plants and those with more severe reductions (OsEPF1oeS). In these plants, both grain yield and above-ground biomass are increased, suggesting that subtle adjustments to SD might be beneficial during drought at the flowering stage  show enhanced A at both ambient and elevated CO2, probably due to a much increased sg  is unchanged, although this may be a signature of the smaller increase in SD (~20%–30%) in these plants relative to Arabidopsis EPFL9-overexpressing plants  are significantly higher than the corresponding average values from 69 lower-yielding accessions  retain the capacity to open and close and changes in SD are often accompanied by inverse changes to stomatal size; i.e., reductions in SD are linked to increases in stomatal size and vice versa . Howeverbdmute plants (which are devoid of SCs) respond more slowly to changes in light intensity  for the fellows.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


It is not surprising that aberrant circRNA expression is common in cancers and they have been implicated in multiple aspects of cancer pathophysiology such as apoptosis, invasion, migration, and proliferation. We summarize the emerging role of circRNAs as biomarkers and therapeutic targets in cancer.Circular RNAs (circRNAs) are rapidly coming to the fore as major regulators of gene expression and cellular functions. They elicit their influence  Some examples of trans-factors are RBPs such as Quaking (QKI), Heterogeneous-nuclear ribonucleoprotein L (HNRNPL), and RNA-binding motif protein 20 (RBM20) (CircRNA formation by back-splicing is facilitated by s (RBPs)  (Jeck ets (RBPs) . ICS facs (RBPs) . In huma (RBM20)  (Conn et (RBM20) . RBPs wh (RBM20)  whereas  (RBM20) .CDR1as, which harbors >70 conserved binding sites for miR-7  and prevents its binding to the cognate linear mRNA resulting in its reduced translation  by PDK1 (3-phosphoinositide-dependent protein kinase 1)  which are translated into short peptides referred to as microproteins . GeneralCircRNAs have several attributes that make them potential biomarkers for cancer diagnosis and prognosis. They are more stable than linear RNAs due to lack of free 5′ and 3′ ends   in AML patients  signaling pathway which is associated with a more immature AML phenotype  mutation used in the validation of CLL prognosis , mutations in ATR, and IRF4 genes, however, its function in MM needs further investigation  level and less advanced International Staging System stage , and treatment response in MM patients  was downregulated in diffuse large B-cell lymphoma (DLBCL) and its levels in plasma can distinguish patients from healthy controls  stage  in CRC patients  and was correlated with poor clinical outcomes  negative status, higher Ki67 index, larger tumor size, and more lymphatic metastasis  stage, abnormal aspartate aminotransferase, abnormal alpha-fetoprotein and abnormal carbohydrate antigen 199 levels  of HCC patients after surgery  was upregulated in HCC patients with higher body fat ratios  resistant patients and predicted poor prognosis  tissues and plasma of patients and was associated with TNM stage and lymphatic metastasis  patients   and is an independent predictor for the survival of NSCLC patients after surgery , lymph node metastasis, and poor OS   and neurofibromin 2 (NF2)  stages and depth of stromal invasion, and indicated poor OS and DFS  for OSC , and distant metastasis and is a potential biomarker for OSC , short hairpin RNAs (shRNAs) or by employing chemically modified antisense oligonucleotides (ASOs) complementary to the back-splice junction, latter is preferred for CircMYBL2 is significantly upregulated in AML patients with FLT3-ITD mutations and it increases the translational efficiency of FLT3 transcript, by facilitating binding of polypyrimidine tract binding protein 1 (PTBP1) to FLT3 transcript , f-circPR, and f-circM9, respectively , an activator of Wnt/β-catenin stabilization   , and silencing it suppressed migration and invasion of BC cells  transcript by sequestering miR-34a, and its knockdown induces apoptosis , and aurora kinase A (AURKA)    and EMT by sponging miR-29a, and stabilizing its target VEGFA in BCa cells , and its knockdown induced cell-cycle arrest, inhibited proliferation and induced apoptosis is OSC cells   expression (Zhao W. et al., circUHRF1 reduces migration, invasion, and EMT of OSCC cells (Zhao W. et al., CDR1as expression is common to several cancer types, and targeting it for treating many different cancer types has shown promising results in vitro and in vivo. Development of RNA-based therapeutics for targeting CDR1as for clinical use has the potential to emerge as a single-target therapy for multiple cancers and is worth further investigation.CircRNAs which were considered mere splicing artifacts until a few years ago are poised to occupy a center stage in the world of regulatory RNAs. CircRNAs regulate the cellular transcriptome by diverse mechanisms and contribute to a range of cellular functions. They are involved in regulating all the major hallmarks of cancer and can serve as promising biomarkers for cancer diagnosis and prognosis. Unfortunately, so far none of these circRNAs have reached the clinics, and evaluation of a combination of circRNAs as a signature for diagnosis and correlation with clinical features is the likely way forward. CircRNAs also have immense potential for use as therapeutic targets. Novel and effective therapies can be designed by either modulating the endogenous expression circRNAs or by exogenous delivery of artificially engineered circRNAs. At present, the use of circRNAs as therapeutic agents is restricted to the bench and warrants further investigation for clinical use. The circRNA which may be suitable for therapeutic targeting, may also be different for distinct cancer types. However, the aberrant PK and VS conceived and designed the manuscript. AR, SB, VS, and PK wrote the manuscript. All authors read and approved the final version of the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Both degeneration and regeneration of dendritic branches involve precise spatiotemporal regulation for the proper wiring of functional networks. In particular, dendrite degeneration must be targeted in a compartmentalized manner to avoid neuronal death. Dysregulation of these developmental processes, in particular dendrite degeneration, is associated with certain types of pathology, injury, and aging. In this article, we review recent progress in our understanding of dendrite degeneration and regeneration, focusing on molecular and cellular mechanisms underlying spatiotemporal control of dendrite remodeling in neural development. We further discuss how developmental dendrite degeneration and regeneration are molecularly and functionally related to dendrite remodeling in pathology, disease, and aging.Dendrites are cellular structures essential for the integration of neuronal information. These elegant but complex structures are highly patterned across the nervous system but vary tremendously in their size and fine architecture, each designed to best serve specific computations within their networks. Recent  These in vivo imaging studies have revealed that developing dendrites often undergo multiple rounds of regeneration and regeneration before the establishment of their final shape  neurons, the nociceptors that sense pain and itch  sensory neurons provide an excellent model to study the molecular and cellular basis for dendrite remodeling as class IV da (C4da) neurons undergo extensive dendrite remodeling during metamorphosis using multiple distinct cellular strategies . RORα was originally identified as the gene responsible for the ataxic mutant mouse The BTB/POZ-type transcription factor BTBD3 is required for dendrite remodeling of the layer IV pyramidal neurons in the rodent barrel cortex  has been implicated in activity-dependent dendrite growth in Drosophila C4da neurons has identified the miRNA miR-87 as a critical regulator of dendrite regeneration  is a functional target for miR-87-mediated repression as ttk69 expression is increased in miR-87 knockout neurons and reducing ttk69 expression restores dendrite regeneration in miR-87 neurons. Given that Ttk69 prevents progenitor cell differentiation by suppressing the expression of genes required for neural fate specification  have recently emerged as key factors regulating developmental timing in the nervous system  have been implicated in regulating the structural plasticity of dendrites C. elegans PVD neurons, an antimicrobial peptide, namely NLP-29, secreted from the epidermis drives aging-associated dendrite degeneration . Time-lapse imaging of pruning dendrites in Drosophila C4da neurons reveals low frequency (~0.01 Hz) Ca2+ transients in dendritic branches that are destined to be pruned  are responsible for generating Ca2+ transients, and mutant C4da neurons lacking the VGCC activity show significant defects in dendrite pruning, suggesting that the dendritic Ca2+ transients are predominantly composed of Ca2+ influx through VGCCs. Given that VGCCs are activated by depolarization of membrane potential, membrane potential might be locally changed in dendritic compartments, which in turn drives Ca2+ transients. Subsequent calcium signaling activates the Ca2+-dependent protease calpains that promote dendrite degeneration cooperatively with the activity of caspases  organization is important for both the degeneration and regeneration of dendritic trees  as a critical factor for dendrite regeneration after injury (Nye et al., A recent study in Drosophila C4da neurons, the first morphological alterations are observable in the proximal regions of dendrites: proximal dendrites actively form varicosities and dendritic branches progressively become thinner, which eventually compartmentalizes distal parts of the dendrites (Williams and Truman, 2+ transients in distal dendrites, suggesting that the local membrane dynamics at proximal dendrites spatially defines dendrite pruning. In addition to the local endocytosis at proximal dendrites, global endocytosis contributes to dendrite pruning in C4da neurons in part through endosomal degradation of the L1-type cell-adhesion molecule Neuroglian (Nrg; Zhang et al., nrg mutant neurons show precocious dendrite pruning. Thus, the removal of Nrg from the cell surface acts as a prerequisite for dendrite pruning. Indeed, genetic evidence suggests that this global endocytosis for Nrg degradation functions in dendrite pruning cooperatively with the local endocytosis for the compartmentalized Ca2+ transients (Kanamori et al., Recent studies in invertebrate models indicate that local membrane dynamics in dendritic branches impact dendrite remodeling. In the course of dendrite pruning in C. elegans PVD neurons (Oren-Suissa et al., The type I membrane protein EFF-1, which was originally identified as a cell fusion-promoting factor, regulates the complexity of dendritic arbors by pruning excessive dendritic branches in in vivo, but many questions remain as to how the sequential rounds of branch degeneration and regeneration in developing dendrites are regulated by coordinated actions of the identified molecules. In particular, spatial regulation of dendrite degeneration and regeneration is still largely elusive. For instance, how the layer IV pyramidal neurons could selectively degenerate and regenerate apical and basal dendrites, respectively, is unknown (in vivo imaging systems to precisely monitor multiple molecular activities in dendrites. Also, studies using Drosophila models have provided several molecular clues that could bridge our knowledge gaps in the spatiotemporal regulation of dendrite remodeling. First, given that microRNAs are the potential factors that drive the temporal transition from dendrite degeneration to regeneration, further identification of the downstream targets should be an efficient way for further understanding of the temporal control. Second, Ca2+ transients and Caspase activity can be good readouts to identify molecules involved in the spatial control of dendrite compartmentalization. The field is only at the starting point in terms of understanding how the components function together in dendrite degeneration and regeneration.In the past decade, considerable progress has been made in understanding the molecular mechanisms underlying dendrite remodeling including branch regeneration and degeneration  unknown . It is e unknown . To tackAll authors made intellectual contributions to the manuscript and wrote the article. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Roots typically grow downward into the soil where they anchor the plant and take up water and nutrients necessary for plant growth and development. While the primary roots usually grow vertically downward, laterals often follow a gravity set point angle that allows them to explore the surrounding environment. These responses can be modified by developmental and environmental cues. This review discusses the molecular mechanisms that govern root gravitropism in flowering plant roots. In this system, the primary site of gravity sensing within the root cap is physically separated from the site of curvature response at the elongation zone. Gravity sensing involves the sedimentation of starch-filled plastids (statoliths) within the columella cells of the root cap (the statocytes), which triggers a relocalization of plasma membrane-associated PIN auxin efflux facilitators to the lower side of the cell. This process is associated with the recruitment of RLD regulators of vesicular trafficking to the lower membrane by LAZY proteins. PIN relocalization leads to the formation of a lateral gradient of auxin across the root cap. Upon transmission to the elongation zone, this auxin gradient triggers a downward curvature. We review the molecular mechanisms that control this process in primary roots and discuss recent insights into the regulation of oblique growth in lateral roots and its impact on root-system architecture, soil exploration and plant adaptation to stressful environments. As sessile organisms, plants have to use directional cues within their environment to grow towards areas that allow them to best perform their primary functions, which include gas exchange, photosynthesis, and reproduction for shoots, and anchorage, water and nutrients uptake for roots. Examples of such cues include gravity, direction of incident light, gradients in water, ions, oxygen, chemicals, and temperature, and impedance to growth, to cite only a few.Gravity is a uniform directional cue on Earth, and acquisition by higher plant roots of rapid mechanisms allowing its detection and use as a growth guide contributed to their successful colonization of land ecosystems . Most hiA plant organ’s GSA is typically dictated by the genetic makeup of the plant and influenced by environmental and/or developmental parameters. For instance, the GSA of lateral roots conditions the radial expansion of the root system. Environmental parameters will often modify this expansion. For instance, drought will typically dictate a narrower root system that is conditioned by a lower lateral root GSA, leading to deeper root systems capable of seeking out water deep underground. On the other hand, accumulation of nutrients such as phosphorus in upper layers of the soil, will promote an increase in lateral root GSA leading to a radial expansion of the root system and allowing better exploration of the upper layers of the soil. These amazing root-system behaviors are important in agriculture as they allow plants to better adapt to the rapid changes that typically occur in their environments, taking maximal advantage of the resources available to them in close proximity.This brief and necessarily incomplete description of plant gravitropic responses illustrates the multiplicity of plant organ responses to this directional cue, emphasizing the importance of developmental and/or environmental parameters in guiding organ interpretation of the gravity signal.To grow, plant organs use a combination of cell division in apical meristems and cell elongation in their elongation zone (EZ). When reoriented within the gravity field, these organs curve back toward their original GSA in a process that involves differential cellular elongation between upper and lower flanks of the EZ. This occurs because plant organs have the ability to sense gravity, transduce the corresponding signal into a biochemical gradient, transmit that gradient to the EZ, and respond by differential cellular elongation between upper and lower flanks of the root. The main objective of this review is to discuss our current understanding of the molecular mechanisms that allow roots to sense the direction of gravity. We also briefly summarize our understanding of the mechanisms that govern signal transmission to the EZ and curvature response.Arabidopsis thaliana roots demonstrated a predominant role for the top two layers in gravity sensing [In roots, gravity sensing occurs primarily in the cap, an organ that covers the root apical meristem. The root cap serves both as a sensor for several environmental cues and as a protective structure preventing meristem damage as the root grows in soil. Several experiments have documented a role for the root cap in gravity sensing. For instance, deleting the root cap , alterin sensing . So, whaA possible answer to this question can be found in the unique organization of these cells. Indeed, root-cap columella cells are rather large and characterized by a central cytoplasm mostly devoid of visible organelles or bundled cytoskeleton elements. The endoplasmic reticulum (ER) and most other organelles line their periphery, with the exception of dense starch-filled plastids (amyloplasts), which are free to sediment to the bottom under the influence of gravity ,7,8. WheSeveral lines of evidence support a role for amyloplast sedimentation and/or repositioning within these cells in gravity sensing. First, studies with starchless and starch-deficient mutants have revealed an important role for amyloplast sedimentation in gravitropism. Starch is denser than the surrounding cytoplasm, providing enough weight for amyloplasts to settle to the lower side of the columella cells. Upon plant reorientation, amyloplasts settle to the new bottom side in wild type plants. On the other hand, in starchless mutants, columella amyloplasts cannot sediment upon gravistimulation, being much lighter. Interestingly, these starchless mutants display substantially altered gravitropic responses, supporting a role for amyloplast sedimentation in gravity sensing ,11,12,13sex1 in Arabidopsis thaliana), or conditions that result in larger amyloplasts, all confer greater sensitivity to gravity [In starch-deficient mutants, a limited amount of starch remains present in the amyloplasts. Yet, the density of these plastids remains insufficient for sedimentation under 1g and root gravitropism is affected. Interestingly, researchers were able to restore a significant level of gravitropic response by subjecting these seedlings to centrifugation, a process that allowed significant sedimentation of starch-deficient plastids . On the  gravity .Equally significant in demonstrating a role for amyloplast displacement/repositioning in gravity signal transduction are experiments involving strong magnetic fields to artificially displace amyloplasts within the columella cells of the root cap. Such displacement is possible because starch is a diamagnetic material susceptible to the ponderomotive force exerted by local high-gradient magnetic fields. When such magnetic fields are applied near plant organs, directed laterally, they promote amyloplast displacement within the statocytes. In vertical roots, lateral magnetophoretic displacement of statocyte amyloplasts led to root-tip curvature in a direction predicted by amyloplast displacement, which is opposite to that induced in shoots ,17.distorted1, lead to slower kinetics of gravitropism [The experiments described above support a role for amyloplast sedimentation in gravisensing. However, it is also important to realize statocyte amyloplasts are not completely free to sediment. In fact, a dynamic actin-filament network appears to also interact transiently with the amyloplasts in these cells. These transient interactions result in saltatory movements that may contribute to or fine-tune the gravitropic response ,18. Consitropism ,22. Alterotato) is set up to maintain the root cap at a defined angle from the vertical over time, the platform will rotate continuously as the root curves, attempting to return the tip to the vertical. If, on the other hand, the rotato is programmed to maintain a subapical region of the root tip at a defined angle from the vertical, the root should curve until it reaches the vertical, at which time the curvature should end, and the platform should stop its rotation. When this experiment was carried out, the tip continued to curve and the platform continued to rotate, overshooting the vertical [While amyloplast sedimentation/repositioning in the root-cap statocytes appears to be the primary mechanism of gravity sensing in roots, a secondary mechanism may also exist in the distal elongation zone . To invevertical . This amvertical .hydrostatic pressure model). A similar mechanism was previously suggested to explain gravity sensing by the large internodal cells of Chara and rice root tips [What is very puzzling about these observations is none of the root DEZ cells contain sedimenting amyloplasts, suggesting the existence of an alternative mechanism of gravity sensing in these cells. One possibility would be DEZ cells can sense gravity by detecting the overall pressure exerted by the protoplast on its wall  postulates sedimenting amyloplasts within the statocytes might interact with the cytoskeleton network, thereby disrupting the distribution of tensions within the cell. Connections between actin filaments and the plasma membrane and cell wall would allow force transfer to the membrane, promoting the opening of mechanosensitive ion channels and initiation of gravity signal transduction [Several models have been proposed to describe the transduction of information derived from amyloplast sedimentation/repositioning within the statocytes into lateral auxin transport, which ultimately leads to a curvature response. The first model suggests the statocytes sense the pressure exerted by sedimenting amyloplasts on sensitive cellular elements (the statolith-pressure model), triggering the opening of mechano-sensitive ion channels . A variasduction .2+, in gravity sensing. Although none of the plant mechanosensitive ion channels identified so far have been shown to contribute to gravitropism [2+ transients in gravity signal transduction. Treatments with extracellular Ca2+ chelators, Ca2+-channel blockers inhibitors of calmodulin and/or Ca2+/calmodulin-dependent protein kinases (such as KN-93), all resulted in altered gravitropism [2+. In fact, recent experiments revealed a role for Ca2+ in modulating the extracellular pH changes that occur along gravistimulated Arabidopsis root tips in response to auxin, a later phase in the gravitropic response [These models suggest a role for mechanosensitive ion channels, possibly selective for Caitropism ,33, MCA1itropism . Contribitropism ,36. Unforesponse .3) has been identified as a potential gravity signal transducer in both shoot and root statocytes, which may be consistent with a role for Ca2+ in gravity signaling. InsP3 levels were found to first fluctuate, then increase at the bottom half of oat coleoptiles and Arabidopsis inflorescence stems upon gravity sensing [3, in Arabidopsis roots, stems, and hypocotyls, caused altered gravitropism [3 with U73122 (a phospholipase C inhibitor) led to altered root gravitropism [Arabidopsis INOSITOL POLYPHOSPHATE 5-PHOSPHATASE 13 gene enhanced gravitropism while reducing endomembrane trafficking [3 in gravity signaling in both shoots and roots. Whether this regulatory process occurs early in the transduction pathway within the statocytes, or late during auxin-gradient translocation to the elongation zone or curvature-response, remains unclear [3 and Ca2+ signaling is less clear in plants than it is in animals [Inositol 1,4,5-trisphosphate  [One major implication of the amyloplast-pressure model of gravity sensing is gravitropism should be sensitive to the intensity of gravistimulation . Howeverr model) . It seemr model) ,46,47.Plant organs are capable of responding to very small inclinations from the vertical, a behavior that would not be expected if the sensor were made of granular particles (the amyloplasts) that sediment to the bottom of the statocytes like sand grains . Indeed,Chara. In this system, simple contacts between sedimenting statoliths and sensitive membranes on the sides of the cells appear sufficient for gravity sensing; a force is not needed [Considering this conclusion, what are the molecular mechanisms that might contribute to inclination sensing in plants? One possibility is statocytes sense the proximity of amyloplasts with specific cellular structures at the sides of the cells, rather than detecting the pressure exerted by sedimenting amyloplasts on specific membranes. For example, such an inclination-sensor model could involve the interaction between a ligand carried by sedimenting amyloplasts and receptors present in sensitive membranes on the sides of the statocytes. Such a ligand-receptor model was originally proposed to explain the gravitropic response of single-cell rhizoids in the green algae t needed . A similt needed . An altet needed . Either t needed .The molecular identities of the hypothesized ligand(s) and gravitropic receptors contributing to gravity sensing in plant statocytes remain unknown. However, we do know activation of this pathway upon plant reorientation within the gravity field leads to an asymmetrical redistribution of auxin across the stimulated organ. We will now review the molecular mechanisms that may contribute to this process. First, we will briefly summarize what we know about the molecular mechanisms that contribute to auxin transport in angiosperm roots.As discussed in the following sections, gravity sensing within the root statocytes triggers the lateral transport of auxin across the root cap, with accumulation at the bottom flank. The resulting lateral auxin gradient is then transported to the EZ where it is responsible for gravitropic curvature. Before we discuss the molecular mechanisms that contribute to polarization of lateral auxin transport within the root cap statocytes in response to gravistimulation, we will introduce the reader to the machinery that mediates auxin transport.In angiosperms, auxin is mostly synthesized in young shoot tissues. From there, it is transported through the vasculature towards the root tip where it mixes with locally synthesized auxin to form a pool that accumulates in the quiescent-center cells and upper tiers of columella cells. From this auxin-maximum center, auxin is redistributed laterally to more peripheral tissues of the root cap, then transported back toward the root elongation zone where it inhibits cell elongation .Auxin transport occurs through columns of cells. Each cell within a column takes up auxin from the apoplast and exports it in a polar fashion. As a weak acid, the main form of auxin in plants, indole-3-acetic acid (IAA), is somewhat protonated in the acidic environment of the apoplast (pH ~5.6), allowing its free diffusion through the plasma membrane . HoweverWhen reaching the cytoplasm, which is neutral, most auxin molecules become ionized a process that prevents free diffusion through the plasma membrane toward the apoplast. Therefore, auxin efflux carriers including members of the PIN family, as well as P-glycoprotein-type transporters, are necessary for auxin export ,53. IntePIN3 and PIN7 genes are expressed in overlapping domains of the root cap columella region /WAVING AGRAVITROPIC ROOTS (WAG) kinases modulate both polar localization and auxin transport ,60,61,62Taken together, these results suggest phosphorylation events modulate both gravity-induced PIN relocalization in the statocytes and/or their auxin-transport activity. It has been suggested gravity-induced PIN3/7 relocalization within the statocytes drives the formation of a lateral auxin gradient, ultimately leading to the gravitropic curvature. However, we cannot yet exclude the possibility gravity-induced PIN3/7 relocalization to the bottom side of statocytes is a consequence of differential activation of auxin efflux . Such a It is interesting to note higher auxin levels in the apoplast have been associated with increased retention of auxin-efflux transporters within the plasma membrane . Furtherpin3 and pin7 single mutants show only slight defects in gravitropism, whereas the double mutants display stronger but still only partially agravitropic phenotypes. Together, these results suggest other transporters may be important for gravity-induced auxin-gradient formation across the root cap.While important for gravitropism, the process of gravity-induced PIN3/7 relocalization within the statocytes is neither essential nor sufficient for the response. Indeed, not all roots stimulated by gravity will display evidence of PIN3/7 relocalization in the statocytes . FurtherArabidopsis thaliana were named altered response to gravity1 (arg1) and arg1-like2 (arl2). Mutant seedlings displayed strong, though partial, defects in root and hypocotyl/shoot gravitropism accompanied by alterations in gravity-induced cytoplasmic alkalinization of the statocytes and an absence of PIN3 relocalization upon gravistimulation [ARG1 and ARL2 in gravity signal transduction within the statocytes, a conclusion reinforced by observations of full phenotypic rescue by targeted expression of a wild type transgene specifically in the statocytes of mutant seedlings [Genetic approaches have been effective at identifying some of the molecular mechanisms that contribute to gravity sensing and initial phases of gravity signal transduction in the root statocytes. The first mutations shown to affect gravity signal transduction in mulation ,71,72,73mulation ,74. Takeeedlings ,74.arg1 mutant seedlings resulted in the identification of two genetic enhancers of arg1 named modifier of arg1-1 (mar1-1) and mar2-1. mar1-1 is a hypomorphic allele of TOC75, a gene that encodes the channel component of plastidic TRANSLOCON ON THE OUTER CHLOROPLAST MEMBRANE (TOC) complex, which mediates the import of cytoplasmic proteins through the outer membrane of plastids. mar2-1 is an hypomorphic mutation of TOC132, which encodes another component of the same TOC complex [mar mutations did not obliterate protein import into the plastids. In fact, mutant root-cap amyloplasts accumulate starch and sediment at wild-type rates upon gravistimulation. This suggests amyloplasts may be playing a more active role in gravity signal transduction, beyond simply sedimenting like rocks in the statocytes [More complex genetic screens taking advantage of the partially agravitropic phenotype displayed by atocytes ,75.toc132 mutant roots identified candidate gravity signal transducers, whose functions remain to be characterized [A ligand-receptor model of gravity sensing postulating sedimenting amyloplasts might carry ligands that interact with receptors on the side of the statocytes to trigger gravity signal transduction, was proposed to explain these observations. However, TOC132 was subsequently ruled out as a possible ligand based on a structure-function analysis of its role in gravitropism . A diffecterized .ADK1 gene strongly affects root gravitropism and PIN3 protein localization in the root cap without altering gravity-induced cytoplasmic alkalinization. Therefore, ADK1 may regulate a step of gravity-signal transduction that controls PIN-protein relocalization within the statocytes but does not contribute to their cytosolic pH responses [Another proteomic analysis of gravity-responding root-tips identified ADENOSINE KINASE 1 (ADK1) as a possible gravity signal transducer. This enzyme catalyzes the phosphorylation of adenosine, a metabolite that is produced by the methyl-donor (AdoMet) cycle and nucleic acid metabolism. A mutation in the esponses . UnfortuLAZY genes and the initial molecular characterization of their roles in gravity signal transduction. The lazy mutation was originally identified as resulting in a prostrate shoot phenotype in rice without affecting amyloplast sedimentation in the statocytes [lazy mutant coleoptiles failed to develop a lateral auxin gradient upon gravistimulation [LAZY1 gene that encodes a plant-specific protein of unknown function (see below). LAZY1 orthologs have been identified and initially characterized in several plant species. In the legume model Medicago truncatula, mutations named negative gravitropic response of roots (ngr), which lead to upward growing roots, were found to affect a LAZY1 ortholog [Probably the most exciting recent development in our investigations of gravity signal transduction in plants is the identification of the atocytes ,78. lazymulation . Subsequortholog .LAZY-like genes have been identified in Arabidopsis thaliana [Arabidopsis LZY genes (LZY1-4) were found to be expressed in the statocytes whereas LZY5 and LZY6 transcripts could not be found [LZY2 and LZY3 are expressed in the statocytes of both shoots and roots whereas LZY1 is mostly expressed in the shoot statocytes (endodermis) and LZY4 in the root tip [LZY3 resulted in altered lateral root growth angle, a phenotype that was exacerbated by bringing the lzy2 mutation in the same background. This phenotype was further enhanced to an upward root phenotype when the lzy4 mutation was added [LZY1 within the statocytes of lzy1 lzy2 lz3 triple mutant plants, which display agravitropic primary stems and downward lateral branches, allowed full rescue of the gravitropic defect, further confirming functional redundantly between members of LZY gene family in Arabidopsis statocytes [Six thaliana . Four ofbe found ,82,83. Aroot tip ,82,83,84root tip ,81,82. Fas added ,81. Signlzy1 lzy2 lzy3 mutant shoots and lzy2 lzy3 lzy4 mutant roots were associated with impaired lateral auxin transport, whereas amyloplast sedimentation in the statocytes remained unaffected [lzy1 lzy2 lzy3 lzy4 quadruple mutants were shown to display normal phototropism, a response that is also dependent upon PIN-mediated lateral auxin transport [The gravitropic defects displayed by affected ,81,82. FThere is currently no clear answer to this question. However, investigations of protein localization and sequence, and identification of interacting partners, may provide meaningful clues to this process. Expression of LAZY proteins fused with GFP showed the proteins localize at the cell periphery, in association with plasma membrane markers, and within the nucleus ,87,88,89LAZY orthologs found in multiple plant species revealed the existence of 5 conserved domains within the protein, named I through V . The functional significance of these regions for plant gravitropism has been investigated by mutating each region within the Arabidopsis AtLAZY1 gene and testing the ability of each mutant allele to rescue the large inflorescence branch angle of mutant plants as well as localizing the mutant protein in plant cells [Protein sequence comparisons between nt cells . Resultsnt cells .LZY2 and LZY3 lacking the CCL domain failed to rescue the gravitropism defect of lzy1 lzy2 lzy3 mutant seedlings [lzy1 lzy2 lzy3 mutant plants resulted in upward-growing roots, a phenotype similar to that of lzy2 lzy3 lzy4 mutant seedlings [Recent functional analysis of region V, also named CCL motif, revealed a possible role for LZY3 protein in recruiting regulators of polar auxin transport to the plasma membrane at the lower side of lateral root cap statocytes upon gravistimulation . In Arabeedlings . Furthereedlings . These eeedlings .Pleckstrin Homology (PH) domain, Regulator of Chromosome Condensation 1 (RCC1)-Like repeats, a Fab1/YGL023/Vps27/EEA1 (FYVE) domain, and a Brevis Radix (BRX) domain. The latter BRX domain of RLD proteins was found to directly interact with the CCL domains of Arabidopsis LZY2 and LZY3 proteins. In Arabidopsis, four RLD genes (RLD1-4) are expressed in the root cap and vascular tissues of the main and young lateral roots. rld1 rld4 double mutants displayed decreased primary root gravitropism and increased lateral root GSA, phenotypes that are associated with decreased PIN3-GFP signal in lateral root-cap statocytes. Furthermore, rld1 rld2 rld3 rld4 quadruple mutants displayed severe embryo-development defects associated with altered vasculature development and decreased PIN1-GFP signal. Together, these data suggest RLDs regulate auxin flow through PIN proteins in both root gravitropism and plant development.LZY CCL-domain-interacting partners were recently identified as RCC1-LIKE DOMAIN (RLDs) proteins, which are conserved amongst land plants and share several domains including a Careful kinetic investigations of cellular localization of functional fluorescent protein tagged versions of LZY3, RLDs and PIN3 within the lateral root cap statocytes of control and gravistimulated wild type and mutant seedlings strongly suggested the LZY3 protein relocalizes to the bottom side of the lateral root cap statocytes upon gravistimulation, where it recruits RLDs. This process then triggers a repolarization of the PIN3 protein to the same side of the statocytes, leading to lateral auxin transport  Figure B.The RLD proteins share a 300–500 amino acid domain (the RLD domain) capable of catalyzing guanine nucleotide exchange on Rab8a, a protein that contributes to post-Golgi trafficking to the plasma membrane along with the exocyst complex ,91,92. Tlzy mutants demonstrated a role for LZY3 in primary root gravitropism as well, redundant with other members of the LZY gene family (see above). Furthermore, rld1 rld4 double mutants displayed decreased primary root gravitropism in addition to their lateral root phenotype [The mechanisms contributing to gravity signal transduction in lateral roots differ significantly from those implicated in primary root gravitropism, as discussed in henotype . Althoughenotype . From thhenotype .One key question that remains unanswered, however, relates to the molecular mechanisms that govern LZY3 protein binding to the plasma membrane in the statocytes and its polarization to the lower side upon gravistimulation. Whether this association is mediated by protein-protein or protein-lipid interactions remains unknown, although the authors speculate the K/R-rich domain found within LZY proteins could contribute to interactions with positively charged anionic phospholipids . It is wArabidopsis thaliana. Indeed, rice OsLAZY1 was also found to interact with OsBRXL4 at the plasma membrane [OsBRXL genes by RNA interference led to a compact plant phenotype due to narrower tiller angles whereas OsBRXL4 over-expression resulted in a prostate growth phenotype due to wider tiller angles [Ethylene-Responsive Element Binding Factor-Associated Amphiphilic Repression (EAR) motif, which has been associated with transcriptional repression [Observations of interactions between LAZY and BRX domain-containing proteins are not limited to membrane . This inr angles . While Lr angles . It is wpression ,89. In fpression .Arabidopsis thaliana, involving a LAZY protein. In roots, light was shown to promote expression of HY5, which binds to enhancers within the LAZY4 gene promoter, leading to increased LAZY4 expression and enhanced positive root gravitropism. In darkness, low HY5 expression resulted in decreased starch accumulation in the statocytes, decreased LAZY4 expression and reduced root gravitropism [LAZY4 expression and inhibition of negative hypocotyl gravitropism [It is well established multiple environmental cues such as light and obstacles modulate the gravitropic response . This implies the gravistimulus-induced lateral auxin gradient has to be transmitted from the root cap to the EZ for this curvature to occur. The mechanisms contributing to auxin gradient translocation toward the DEZ have been well investigated, leading to the conclusion this gravity-induced auxin gradient is not only propagated quite effectively between site of gradient formation and locale of curvature response, but it is also expanded in the process.In roots, the shootward transport of auxin occurs in peripheral tissues including the lateral root cap, epidermis and cortex C,D. In tGOLVEN1 (GLV1) and GLV2 by cells on the lower side, which trigger a response pathway that also favors PIN2 association with the plasma membrane [Like other PIN proteins, PIN2 is constantly recycled between plasma membrane and endosome C,D. The membrane . Furthermembrane . On the membrane . Hence, membrane .AUX1 gene is broadly expressed in the root tip, including the provasculature, root-cap, and epidermal cells. However, restricting its expression to the lateral-cap and epidermal cells of the root tip is sufficient to rescue the altered root gravitropism phenotype displayed by aux1 mutant seedlings, indicating it functions in these tissues to modulate root gravitropism [The auxin-induced increase in alkalinization of the apoplast on the lower side of a graviresponding root may also contribute to auxin gradient regulation. Indeed, it may trigger a decrease in the fraction of protonated IAA molecules in the apoplast, thereby decreasing the rate of free diffusion through the plasma membrane of transporting cells. Consequently, the auxin influx carrier AUX1 is needed for adequate shootward auxin transport and root gravitropism ,101. Theitropism .Arabidopsis pin2 mutant roots retain some gravitropic capability [Arabidopsis AtPGP1 and AtPGP19 are also expressed in the root EZ, and functional studies in heterologous systems such as plant protoplasts, yeast and mammalian cells, have demonstrated their ability to transport auxin [Considering the preceding discussion, which strongly emphasizes a key role for Arabidopsis PIN2 in directing rootward transport of auxin from cap to elongation zone during gravitropism, it is quite surprising pability . This surt auxin ,103,104.axr3-1) in epidermal cells of the EZ is sufficient to obliterate the gravitropic response whereas expressing it in different cell types has little impact [The auxin-transport mechanisms described in the previous section allow transmission of the gravistimulus-induced lateral auxin gradient between the root cap and the EZ where it triggers differential cellular elongation between upper and lower flanks within 10 to 15 min of stimulation, leading to downward gravitropic curvature. The epidermis appears to be the main driver of root-tip curvature. Indeed, expressing an auxin-response repressor (e impact . Therefo2+ 14 (CNGC14) channel, leading to Ca2+ influx into the cytoplasm and consequent activation of a plasma-membrane H+/OH− conductance  accumulates on the lower side of gravistimulated roots where it inhibits auxin transport and modulates auxin signaling through S-nitrosylation of TIR1 . SimilarThe upper flank of the EZ is exposed to lower auxin levels upon gravistimulation, resulting in increased cell-wall acidity D. IncreaDR5-GFP and dII-VENUS, have demonstrated the auxin gradient generated across the root cap and transmitted to the EZ disappears when the tip reaches an approximate angle of 500 from vertical. At this angle, the amyloplast statoliths have returned to the distal side of the statocytes and the gravity-induced polarity of PIN3/7 proteins has disappeared, being replaced by a symmetrical distribution on all sides of the cells [Ultimately, increased cell elongation on the topside and decreased elongation at the bottom result in downward tip curvature ,109. Thihe cells . From thhe cells . One posThe architecture of a root system defines its ability to either survey shallow areas of the soil for nutrients uptake or dig deeper underground to seek out buried resources such as water during drought periods. While the primary roots of most plants have a tendency to grow orthogravitropically , the lateral roots emerging from the primaries tend to grow either diagravitropically , or plagiogravitropically (obliquely), allowing for broader soil exploration for water and nutrients .Arabidopsis, lateral roots emerge at a 90-degree angle from the primary root, then acquire plagiogravitropism as starch builds up within statocyte amyloplasts and the EZ becomes established [In ablished ,112,113.Arabidopsis thaliana. Regulation of auxin transport and levels in lateral root statocytes seems responsible for GSA specification. Early after emergence, only PIN3 is expressed in the columella cells of lateral root caps where it is quickly redistributed toward the bottom side. As discussed in the previous section, PIN3 relocalization is preceded by a polarization of LZY3 to the lower membrane where it recruits RLD proteins from the cytoplasm. RLD controls the vesicular trafficking of PIN3 leading to its polarization to the bottom membrane of the statocytes [These successive phases of lateral root gravitropism have been investigated in atocytes , lateralPIN3 expression decreases, and PIN4 and PIN7 are activated to very low expression levels. At this stage, the overall level of PIN expression in the statocytes is low, and the PIN proteins are symmetrically distributed on all sides allowing the laterals to continue growing straight along the GSA.When the young lateral root reaches its first GSA plateau, lzy2 lzy3 lzy4 triple mutant roots, which show opposite GSA relative to wild type [lzy mutant plants that express a mutated form of AtLAZY1 carrying two conserved amino acid substitutions in region II of the protein [This initial phase of plagiogravitropic growth may result from an auxin-dependent antigravitropic offset mechanism that opposes gravitropism to regulate the distribution of auxin levels and response between opposing sides . This ofild type ,90,115,  protein , and inv protein .LAZY1 family of genes, plant genomes also contain other genes that encode proteins sharing region II with LAZY1, but lacking domain V [TILLER ANGLE CONTROL 1 (TAC1), which encodes a LAZY-like protein lacking region V, was recently found to oppose LAZY by increasing tiller angle in rice, and branch angles in peach trees and Arabidopsis inflorescences in response to light [lzy2 lzy3 lzy4 and their characterization may yield interesting new insights into the machinery that governs the antigravitropic offset mechanism in lateral roots [In addition to the domain V ,119. Amoto light ,119,120.to light . Recent al roots .PIN4 and PIN7 genes, whose proteins polarize to the bottom side of the statocytes. This PIN-protein relocalization leads to the formation of a lateral auxin gradient that is transmitted to the EZ where it is responsible for a new phase of downward curvature [Arabidopsis thaliana.At the end of the plagiogravitropism plateau phase, an increase in auxin levels and signaling within the lateral-root tip leads to a derepression of the urvature ,121. IniPIN gene family modulate distinct phases of radial root-system expansion, a process that may be targeted by developmental and environmental signals that dictate whether a root system will be radially expanded or axially organized [In conclusion, several members of the rganized . A betteRecent advances in our understanding of the molecular mechanisms that modulate the various phases of root gravitropism have resulted from careful genetic and cell biological investigations of the process in multiple model organisms. Careful investigations of gravitropic sensitivity to pressure and inclination angles have suggested a mechanism of gravity sensing depends upon inclination rather than pressure, and further work will be needed to identify the molecular players in this process. Several studies have revealed a key role for LAZY-family proteins in linking amyloplast sedimentation to gravity-induced polarization of PIN proteins to the lower membrane of the statocytes. Through recruitment of RLD regulators of vesicular trafficking, these LAZY proteins appear to directly target PIN3  transcytosis to the lower membrane, thereby establishing a lateral auxin transport across the root cap ultimately responsible for tip curvature upon transmission to the EZ. It will be very interesting to identify the molecular mechanisms that lead to LAZY targeting to the lower membrane of the statocytes upon gravistimulation. Is it modulated by protein-protein interactions, alterations in lipid composition of the membrane at that location, or other processes such as posttranslational modifications?Novel discoveries have also expanded our understanding of the molecular mechanisms that allow propagation of the gravity-induced lateral auxin gradient between root cap and EZ, and its enhancement through an auxin-dependent feedback regulation of PIN association with the plasma membrane on the lower side of the root. Here, a better understanding of the auxin receptor(s) responsible for this process is needed. Finally, molecules that transduce the signal associated with the lateral auxin gradient into differential cellular elongation on opposite flanks of the DEZ have been identified and initially characterized. However, more investigations will also be needed to identify the molecules that serve as auxin receptors for this process, their location on the surface and/or within the cell, and their mode of action.Our understanding of the mechanisms that modulate root gravitropism in response to other environmental cues has also expanded quite substantially in the last few years. In this review, we discussed the involvement of key light-responsive transcription factors related to PIF and HY5 in the regulation of Arabidopsis hypocotyl and root gravitropism via their impact on LAZY4 expression in the corresponding statocytes, thereby enabling phototropism when needed . EffectsFinally, at a time of great hope for space exploration and colonization of other planets, attention is currently given to investigations of plant responses to microgravity, fractional gravity, and hypergravity conditions. This is because plants have been recognized as key components of bioregenerative life-support systems allowing food, feed, and fiber production along with wastewater and air recycling. Better understanding plant responses to altered gravity conditions will allow the development of efficient plant-based bioregenerative life-support systems. Interestingly, experiments under microgravity have revealed new tropic responses to alternative directional cues such as oxygen  and lighExposure to low gravity level, such as that encountered on the Moon (0.18 g) or under microgravity, resulted in developmental abnormalities associated with structural stress at the plasma membrane and cell wall, along with oxidative stress ,130,131.


Therefore, Mobilan is well-tolerated and induces the expected pharmacodynamic response in humans. These results support further clinical development of Mobilan as a novel immunotherapy for prostate cancer.Toll-like receptor 5 (TLR5) controls endogenous immune responses to pathogens and is a promising target for pharmacological stimulation of anti-tumor immunity. Mobilan is an innovative gene therapy agent consisting of a non-replicating bicistronic adenovirus directing constitutive expression of human Toll-like receptor 5 (TLR5) and the secreted flagellin-based TLR5 agonist, 502s. In mice, Mobilan injection into prostate tumors resulted in autocrine TLR5 signaling, immune system activation, and suppression of tumor growth and metastasis. Here we report a first-in-human placebo-controlled clinical study of Mobilan aimed at evaluating safety, tolerability, pharmacokinetics and pharmacodynamics of a single intra-prostate injection of Mobilan in early stage prostate cancer patients. Mobilan was safe and well-tolerated at all tested doses; thus, the maximum tolerated dose was not identified. Injection of Mobilan induced signs of self-resolving inflammation not present in placebo-injected patients, including transient elevation of PSA and cytokine  levels, and increased lymphoid infiltration in prostate tissue. The highest dose of Mobilan (10 Prostate cancer (PC) is the fourth most common type of malignant neoplasm in the world, being surpassed only by breast, lung and colorectal cancers. In men, only lung cancer is more prevalent. 1.3 million new PC diagnoses were made worldwide in 2018. In the United States (US), an annual incidence rate of ~170,000 makes PC the most common of all cancers in males (excluding non-melanoma skin cancers) . In addiApproaches for treating localized PC include conventional methods such as delayed treatment (expectant management or active surveillance), radical prostatectomy (RPE), radical radiotherapy, and hormone therapy, as well as a number of experimental methods  , 6.Gene therapy-mediated immunotherapy is a promising novel approach to treatment of many types of cancer, including prostate cancer , 8. In g® in the USA , which was conducted for all study subjects prior to their enrollment to confirm their PC diagnosis.For this study, mobilan was injected bilaterally into both lobes of the prostate using ultrasound as a guide. Bilateral injection was selected over unilateral injection based on the assumption that it would provide more intense activation of the immune system and recruitment of immune cells into different regions of the prostate gland as foci of Mobilan-induced TLR5 signaling formed. Furthermore, sextant biopsy data currently do not allow unambiguous localization of prostate cancer, as indicated by the high percentage (72%) of false-positive diagnoses of unilateral cancer revealed by retrospective analysis . In partSince some cell types in mammals  normally express TLR5 and TLR5 agonists are safe within a clinically determined permissible range, it is fair to suggest that safety will be evaluated for Mobilan injected into patients’ prostate. For example, the study to assess safety of a similar immunotherapeutic drug based on adenoviral vector for treating prostate cancer upon intraprostatic administration showed no significant drug-related adverse events or delayed toxicity during a long-term follow-up .In this study, most of the observed AEs were abnormal laboratory values characterized as Grade 1 or Grade 2 according to the CTCAE classification system and were not accompanied by any clinical symptoms or patients’ complaints. Most of the clinically significant elevations in laboratory values appeared to result from the effect of the IP. Nevertheless, we conclude that Mobilan demonstrated satisfactory safety and tolerability at all doses analyzed in this study. The finding that all tested doses of Mobilan were safe indicates that the maximum tolerated dose (MTD) was not reached in this study. It should be noted that the highest Mobilan dose level tested here corresponds to the maximum concentration of the drug that can be obtained during its production.in vivo activity that is intimately connected to its mechanism of action. It should be noted that the lag observed between Mobilan administration and cytokine induction in this study (48 hours) was longer than that seen after injection of the TLR5 agonist entolimod [The study also demonstrated that intraprostatic injection of Mobilan had the expected pharmacodynamic effects on a number of parameters confirming functionality of the construct and representing its known mechanism of action as an immunoregulatory agent. Thus, Mobilan (but not placebo) injection led to temporal elevation of total PSA levels and plasma cytokine  levels, elevation of anti-502s antibody titer, and an increased degree of lymphoid infiltration and aggressiveness of lymphoid infiltration in prostate tissue. Importantly, it was demonstrated previously that the presence of anti-502s antibodies, while confirming expression of 502s, does not interfere with the ability of Mobilan to activate TLR5 signaling in infected cells . Mobilanntolimod . It is lWhile there were several positive pharmacodynamic indications of Mobilan activity in the patients in this study, we did not observe a clear effect of the drug on tumor Gleason score which would suggest a therapeutic effect. Mobilan-treated and placebo-treated patients exhibited a similar decrease in the degree of cell differentiation estimated by the Gleason scoring system over the course of the study. However, since an effect of the IP on cell differentiation may take longer to develop than the time frame of this study, we were not able to draw any unambiguous conclusions from this analysis.11 particles.Also, it is fair to conclude that the optimal correlation between safety parameters and pharmacodynamic parameters  was observed for patients in cohort 5 treated with an injection of Mobilan at a dose of 1 × 10Therefore, the results of this first-in-human clinical trial provide strong support for further development of Mobilan as a PC treatment. This addresses the critical need for new anticancer drugs that persists despite our improved understanding of the mechanisms controlling development and progression of malignant neoplasms. New strategies are needed to overcome the issues of tumor cells’ acquisition of resistance to therapy and tolerance to the body’s immune system as well as the high toxicity of many existing anticancer drugs that limits their therapeutic effects within permissible dose ranges. Key advantages of Mobilan over existing PC solutions  are (i) local delivery via 1–2 injections vs. systemic treatment involving multiple doses, (ii) a favorable toxicity profile, and (iii) the possibility of targeting both hormone-dependent and hormone-resistant cancer. Moreover, the mechanism of action of Mobilan suggests that it may have synergistic effects when administered in conjunction with existing anticancer drugs, particularly immune checkpoint inhibitors such as PD-1 inhibitors  or CTLA-4 inhibitors (Yervoy). Further study of such combinations in preclinical models of PC or other cancers may lead to expansion of the potential therapeutic applications of Mobilan.The investigational product (IP) Mobilan (M–VM3) is a recombinant non-replicating bicistronic adenovirus that directs expression of the human Toll-like receptor 5 (hTLR5) protein and a specific TLR5 ligand, the flagellin derivative 502s .12 viral particles/ml), which is then diluted to prepare working solutions for intratumor injection. The pilot batch of Mobilan for clinical trials was produced by IMMAPHARMA LLC (Russian Federation) in compliance with Good Manufacturing Practice (GMP) regulations. Mobilan particles were produced by homologous recombination using a human embryonic kidney cell culture transformed with the E1 region of human adenovirus serotype 5 (HEK293) followed by stepwise chromatographic purification. One ml of Mobilan stock solution contains the active pharmaceutical ingredient, 1012 physical MOBILAN viral particles (corresponding to 1010 plaque-forming units), and the following excipients: tris (hydroxymethyl) aminomethane, 2.424 mg; sodium chloride, 1.46 mg; glycerol, 0.025 mg; and water for injection, up to 1 ml. The number of replication-competent particles was meticulously verified during quality control and release testing for each batch of Mobilan. The Mobilan stock solution is stored at –70°C and thawed and diluted with 5% glucose solution to the required concentrations immediately before administration.Mobilan is produced as a concentrated stock solution Patient's ECOG performance status 0–2Negative serological tests for HIV, viral hepatitis B and C, and syphilisThe patient and his partner must agree to use barrier contraceptive methods for the duration of the study.Failure to obtain informed consentClinical or radiographic signs of metastatic diseaseIndications for hormone therapy of prostate cancerClinically relevant cardiovascular diseases:Myocardial infarction within 6 months prior to screeningUnstable angina within 3 months prior to screeningSevere insufficient blood circulation (grade III)Clinically relevant heart rhythm disordersHypotension (systolic blood pressure < 86 mm Hg) or bradycardia with HR < 50 bmpUncontrolled hypertension (systolic blood pressure > 170 mm Hg or diastolic blood pressure > 105 mm Hg)Past history of clinically relevant central nervous system diseases by the time screening is performed.Existing infection or other severe or systemic disease increasing the risk of therapy complications.Past history of pituitary or adrenal insufficiency.Other malignant tumors within the past 5 years.Past history of other relevant concurrent diseases that, in Investigator’s opinion, can be aggravated during the study, including uncontrolled diabetes mellitus, rectal disorders, rectal fissures, hemorrhoids, rectal polyps, rectal strictures, and inflammation of the urogenital system: chronic prostatitis, cystitis, urethral catheter, and chronic retention of urine.Positive allergic history, systemic allergic reactions, any alimentary allergy, intolerance, restrictions or special diets that, in Investigator’s opinion, may be a contraindication for participation of the subject in this study.Administration of drugs having a pronounced effect on the immune system within 3 months prior to screening, long-term administration of disaggregants .The patient is currently participating in other clinical trials or was administering IP within 30 days prior to screening, or had persistent adverse drug reactions from any IP.Any clinically relevant abnormal patient’s condition and/or laboratory values not mentioned in the Protocol and revealed at screening and/or any reason that, in Investigator’s opinion, can impede patient’s participation in the trial.Drug or alcohol abuse (at screening or past abuse), which makes the patient ineligible for trial participation in Investigator’s opinion; consumption of more than 5 units of alcohol per week  or previous alcoholism, drug addiction, drug abuse and/or past history of severe alcohol dependence or excessive use of drugs causing drug dependence within one year prior to screening visit.Vaccination within 14 days prior to study initiationSmoking more than 10 cigarettes per dayInability to understand or follow study instructionsPatient is unavailable for surveillance within 29 days after IP administration or is unable to adhere to the study visit schedule.Idiosyncratic reaction to the components of IP.Presence or absence of dose-limiting toxicity, frequency and intensity of adverse events (according to the CTCAE classification ), the nuhttps://www.graphpad.com/).The level of Mobilan expression vector in patient’s peripheral blood determined by validated qPCR assay was selected as pharmacokynetics endpoint. Serial dilution of DNA of Mobilan with the known copy number was performed; a pair of primers for amplification and the optimal conditions ensuring the desired amplification efficiency and linearity within the range between 11 and 3E+06 copies were selected: the calculated amplification efficiency was 95% and the coefficient of determination was 0.997. Mobilan DNA was detected within the entire tested range, from 1E+09 to 3.8E+03 particles per extraction point (from 200 μl of blood); hence, the detection threshold was 3.8E+03 particles per extraction point from 200 μl of blood. The calculated amplification efficiency for the calibration curve of Mobilan isolated from donor’s blood was 100.0%; the coefficient of determination was 0.99. Parameters of the calibration curve are fitted by linear curve; therefore, the linear region of the method is between 3.8E+03 and 1E+09 particles per extraction point. The mean percentage of extraction of Mobilan DNA from blood was 27% . The specificity of the method for quantifying Mobilan DNA in blood was confirmed in blood of 6 donors with no Mobilan added: in the control blood samples from all donors not treated with Mobilan, no Mobilan DNA was detected. No cross-contamination between the wells containing and not containing Mobilan was revealed when extracting Mobilan DNA. Furthermore, no bias in the level of Mobilan detected in blood of different donors, which could have been caused by different degrees of extraction of Mobilan DNA from blood of different donors and other similar reasons, was detected. The results were analyzed using Prism 5.02 software (Pharmacodynamic parameters determined in the study included an assessment of the level of prostate-specific antigen, immune cell count in patient’s whole blood evaluated by flow cytometry, histopathological evaluation of changes in the structure of prostate tissue using the Gleason score and assessment of the degree of lymphoid infiltration and the aggressiveness of the infiltration using the Irani scale  (if pros


With advances in neonatal care, survival of premature infants at the limits of viability has improved significantly. Despite these improvement in mortality, infants born at 22–24 weeks gestation are at a very high risk for short- and long-term morbidities associated with prematurity. Many of these diseases have been attributed to abnormalities of tissue oxygenation and perfusion. Near-infrared spectroscopy utilizes the unique absorption properties of oxyhemoglobin and deoxyhemoglobin to provide an assessment of regional tissue oxygen saturation, which can be used to calculate the fractional tissue oxygen extraction. This allows for a non-invasive way to monitor tissue oxygen consumption and enables targeted hemodynamic management. This mini-review provides a brief and complete overview of the background and physiology of near-infrared spectroscopy, practical use in extremely preterm infants, and potential applications in the neonatal intensive care unit. In this mini-review, we aim to summarize the three primary application sites for near-infrared spectroscopy, disease-specific indications, and available literature regarding use in extremely preterm infants. Near-infrared energy exists in the 700–1,000 nm wavelength spectrum and was first discovered by the German astronomer (and composer) William Herschel in the 19th century , 3. Deox2) as a ratio of oxyhemoglobin/(deoxyhemoglobin + oxyhemoglobin) (The conformations of deoxy- and oxyhemoglobin display distinct spectroscopic properties and absorption spectra . NIRS seoglobin) , 9.2 at a tissue depth of 1–2 cm for the entire microcirculation. rSO2 is reported as a weighted average of the ratio and therefore, approximately 75–85% of the rSO2 reflects the ratio of oxyhemoglobin to total hemoglobin in tissue-specific venules (2), rSO2 can be used to determine the local balance of oxygen delivery and consumption, similar to the mixed venous saturation (SvO2). rSO2 can be used to calculate the tissue fractional tissue oxygen extraction (FTOE), using the formula FTOE = (SaO2 – rSO2)/SaO2  and two down-stream photoreceptors, which measure light absorbance at different tissue depths . Absorpt venules . When coO2)/SaO2 , 14. rSOpatients . Unlike 2 (crSO2), renal rSO2 (rrSO2), and splanchnic rSO2 (srSO2). NIRS probes for crSO2 monitoring are placed midline on the forehead to monitor the frontal lobe gray matter  and white matter injury (WMI) . Due to 2 range  to detect differences in clinical outcomes with respect to continuous crSO2 monitoring in extremely preterm infants.A Cochrane review in 2017 found only one randomized clinical trial looking at the use of cerebral NIRS in preterm infants. While their conclusion did not demonstrate any positive effects of the use of NIRS in preventing brain injury, this study was only powered to detect differences in cerebral oxygenation with the use of NIRS . In fact2 range . In the vere IVH . The Saf2 are associated with swings in cerebral blood flow, the use of NIRS in mechanically ventilated extremely preterm infants may help to detect and correct these changes before injury can occur , hypoglycemia, anemia, and cortical thinning from post-hemorrhagic hydrocephalus . In 2019 Bonsante et al. became the first to demonstrate the correlation between rrSOt of AKI . Until rt of AKI –65. Elevt of AKI . Utilizi2 correlated with other established measures of oxygenation and perfusion, including lactate, gastric pH, and SvO2 . Using a cohort of 100 preterm infants <32 weeks gestation, Patel et al. showed that the mean srSO 2 weeks . Additioto crSO2 , and varto crSO2  have beeated NEC .2 and decrease splanchnic FTOE in extremely preterm infants (2 when infants receive feeds during a transfusion have not been consistently shown, with some studies demonstrating no change (2 compared to those who did not develop NEC (A final area of interest is the use of splanchnic NIRS in anemic preterm neonates receiving blood transfusions to further understand the association between NEC and blood transfusions. Blood transfusions have been shown to improve srSO infants –43. Chano change  and otheo change . Very loelop NEC . Additio2 and the underlying physiology that could be driving these changes (2 values begin to deviate from the “norm.”The use of NIRS in preventing cerebral injury in extremely preterm infants remains an active area of challenging research, particularly as it pertains to establishing normative values and consensus within neonatology. The use of “pattern recognition” has often been suggested as a stop-gap measure, that is, recognizing trends in crSO changes . The man2 using a pediatric or neonatal sensor when compared to an adult sensor, so close attention should be paid to the type of sensor used when interpreting absolute value rSO2 results provided in a study (While much of the research using NIRS in preterm infants has focused on cerebral NIRS, renal and splanchnic NIRS also have emerging data and potential for clinical and research opportunities. Further studies need to be performed to validate the use of NIRS and determine the appropriate use of this technology, but the possibility of having a non-invasive method of monitoring tissue-level hemodynamics and oxygen balance makes this research a worthwhile endeavor. One key consideration in research and clinical application is the specific NIRS device and sensor used, as there are multiple manufacturers and sizes of sensors. One study has shown consistently higher crSO a study .Many studies, even those focused on extremely preterm infants, do not include the most immature babies between 22 and 24 weeks gestation. As this is the patient population at the highest risk of morbidities and mortality associated with prematurity, they stand to benefit the most from precise management of hemodynamic status and monitoring for complications. Outcomes-driven research will ultimately determine if the use of NIRS will become mainstream in most institutions, but the use of regional perfusion monitoring to potentially prevent devastating morbidities is exciting and worth the effort.All authors contributed to the conception and design of this manuscript, drafting and critically revising the initial manuscript, and approval of the final version. All authors are accountable for all aspects of the work.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Which patient-reported outcome measures have been used to evaluate global and individual domains of postpartum recovery?In this systematic review, 573 studies were included that used 233 patient-reported outcome measures (201 specific to outpatient studies) to assess postpartum recovery.Patient-reported outcome measure use among studies assessing postpartum recovery is heterogeneous, which highlights the need to psychometrically evaluate the quality of available patient-reported outcome measures to formulate recommendations regarding which instruments to use. Despite the global delivery rate being approximately 259 deliveries per minute in 2018, postpartum recovery remains poorly defined.To identify validated patient-reported outcome measures (PROMs) used to assess outpatient and inpatient postpartum recovery, evaluate frequency of PROM use, report the proportion of identified PROMs used within each recovery domain, report the number of published studies within each recovery domain, summarize descriptive data  for published studies using PROMs to evaluate postpartum recovery, and report PROMs used to evaluate global postpartum recovery.This study followed PRISMA-ScR guidelines. A literature search of 4 databases  was performed on July 1, 2019, to identify PROMs used to evaluate 12 author-defined domains of postpartum recovery. All psychometrically evaluated PROMs used to evaluate inpatient or outpatient postpartum recovery after all delivery modes were included.From 8008 screened titles and abstracts, 573 studies (515 outpatient and 58 inpatient) were identified in this review. A total of 201 PROMs were used to assess recovery for outpatient studies and 73 PROMs were used to assess recovery for inpatient studies. The top 5 domains (with highest to lowest numbers of PROMs) used to assess outpatient recovery were psychosocial distress (77 PROMs), surgical complications (26 PROMs), psychosocial support (27 PROMs), motherhood experience (16 PROMs), and sexual function (13 PROMs). Among inpatient studies, the top 5 domains were psychosocial distress (32 PROMs), motherhood experience (7 PROMs), psychosocial support (5 PROMs), fatigue (5 PROMs), and cognition (3 PROMs). The 3 most frequently used PROMs were the Edinburgh Postnatal Depression Scale (267 studies), Short-Form 36 Health Questionnaire , and Female Sexual Function Index (35 studies). A total of 24 global recovery PROMs were identified among all included studies. Most studies were undertaken in the United States within the last decade and were published in psychiatry and obstetrics and gynecology journals.Most PROMs identified in this review evaluated a single domain of recovery. Future research should focus on determining the psychometric properties of individual and global recovery PROMs identified in this review to provide recommendations regarding optimum measures of postpartum recovery. This systematic review identifies patient-reported outcome measures (PROMs) used to evaluate global and individual domains of postpartum recovery. Recommendations regarding obstetric enhanced recovery have thus far focused on antepartum and inpatient postpartum care after cesarean delivery.5 Inpatient and outpatient postpartum recovery remain poorly defined. Approximately 10% of women undergoing cesarean delivery do not recover  by day 50 postpartum.6 Poor postpartum recovery can affect families, health care systems, society, and decisions made regarding future childbirth.In 2018, the world birth rate was approximately 259 deliveries per minute.8 and correlate with surgery duration and complexity.10 Value-based reimbursements based on perioperative PROM data have also been introduced into health care systems such as the National Health Service.11 To our knowledge, few PROMs have been developed to assess global inpatient and outpatient postpartum recovery. This may be partly because after hospital discharge, focus rapidly shifts from maternal well-being to neonatal feeding and development, in addition to recovery being difficult to define and multifactorial.Patient-reported outcome measures (PROMs) are structured questionnaires allowing patients to report their health status. The Quality of Recovery (QoR)–40 and QoR-15 are examples of clinically useful PROMs, which accurately measure nonobstetric postoperative quality of recovery12 However, this tool has only been validated for use up to 24 hours after delivery and did not include measures of psychological recovery.A systematic review (involving authors from this review) concluded that the Obstetric Quality of Recovery–11 scoring tool (ObsQoR-11) was the best PROM to assess functional recovery after cesarean delivery, as assessed by measures of validity, reliability, and responsiveness.The aims of this scoping review were to identify PROMs used to evaluate outpatient and inpatient recovery after childbirth, evaluate the frequency of PROM use, summarize descriptive data of included studies , and identify global recovery PROMs .12 and matching them with all possible available subject headings and key words. Searches were created for each domain and reviewed by the group to supplement any missing ideas or key words. Individual domain searches were then combined into the larger search. The search strategy included terms and alternative spellings related to cesarean delivery, spontaneous vaginal delivery, and assisted vaginal delivery, in addition to evaluation methods and recovery of function. A detailed search strategy is provided in eMethods 1 in the 13A medical librarian (L.B.) performed a literature search with no language restriction and without the use of date limiters on July 1, 2019, using the MEDLINE through PubMed, Embase, Web of Science, and CINAHL databases. Subjective PROMs of recovery after childbirth via all delivery modes were sought. The search strategy was composed by reviewing the 12 recovery domains proposed by Sharawi et al14 Three authors  evaluated validation status of reviewed PROMs. We included all study designs including PROMs mentioned in review articles. If a PROM included more than 3 recovery domains assessing elements of global recovery  rather than recovery associated with a specific domain, it was termed a global recovery measure. The EuroQoL (EQ-5D-3L) PROM, for example, measures global health status through 5 domains and is therefore a global recovery measure. However, the Oswestry Disability Index is a PROM assessing “pain” because it specifically assesses the association of pain with several domains , rather than how these domains are associated with the patient’s overall global health state. Absence of evidence of a validation process  resulted in exclusion of the PROM. We excluded PROMs evaluating satisfaction, patient experience, and measures of antenatal, labor, or predelivery experience, and excluded objective health care worker–assessed measures of recovery such as the Bromage Motor Blockade score,15 Ramsey Sedation scale score,16 and LATCH  score.17PROMs were included if they had been psychometrically evaluated  in either an obstetric or nonobstetric study population. A PROM was considered to be validated if the study itself or another published article reported at least 1 measure of validity, reliability, or responsiveness as described by the COSMIN  group.18 All abstracts were reviewed by a minimum of 2 of us. Any disagreements were discussed among 4 authors  until all team members agreed. Because of the volume of studies we anticipated that would require screening, we elected to include studies only if the validated PROM name was explicitly mentioned in the article title or within the abstract of a fully published article. Outpatient studies required reference to an outpatient, community or clinic  setting, or the reporting of PROM time points beyond 5 days postpartum. A standardized data collection tool was used by 8 authors  to extract PROM data from the included studies. PROMs were assigned to individual domains by 3 authors . Further opinion was obtained when necessary from 1 additional author (B.C.). Per PRISMA-ScR guidance, evaluation of quality of evidence of included studies was outside the scope of this review. Studies containing a PROM and meeting the above inclusion criteria had the following data extracted: year the study was published, country of the study, journal specialty type, and PROM used to assess inpatient or outpatient (or both) recovery. Relevant extracted data were entered into an Excel spreadsheet and graphs were made using Microsoft Excel,version 14.7.7 (Microsoft Corp).After removal of duplicates and animal studies, articles were entered into the Rayyan reviewing system online.The outcome measures included identification of validated outpatient and inpatient recovery scoring tools after all modes of delivery, frequency of PROM use among included studies, proportion of identified PROMs within each domain that were used for inpatient and outpatient assessment of recovery, descriptive data regarding published studies , and identification of global recovery PROMs for outpatient and inpatient studies. For the identified global postpartum recovery PROMs that were developed and validated for use in this setting, we also sought to evalulate the frequency of their use and the number of domains evaluated by each PROM.The literature search identified 10 212 publications, reduced to 8008 after removal of duplicates and animal studies. The summary of the search is provided in Among the 515 studies that evaluated outpatient recovery , surgical complications (26), psychosocial support (27), motherhood experience (16), sexual function (13), pain (8), sleep (7), fatigue (5), physical function (2), breastfeeding and breast health (2), scar and wound healing (1), and cognition (0). Furthermore, 6 domains  lacked PROMs developed for specific use to assess recovery in the postpartum outpatient population. The domains with the highest to lowest numbers of PROMs used to evaluate inpatient recovery domains were psychosocial distress (32), motherhood experience (7), psychosocial support (5), fatigue (5), cognition (3), breastfeeding and breast health (2), pain (2), physical function (2), sexual function (1), sleep (1), scar and wound healing (0), and surgical complications (0).19 the State Trait Anxiety Inventory,20 and the Impact of Event scale.21The 3 most frequently used PROMs were the Edinburgh Postnatal Depression Scale (267 studies), Short-Form 36 Health Questionnaire , and Female Sexual Function Index (35 studies). The numbers of outpatient studies  using PROMs within each domain are reported in Most outpatient and inpatient recovery studies were undertaken in the United States and published in psychiatry and obstetric and gynecology journals . More th22 and the remaining 6 were standardized PROMs: Inventory of Functional Status After Childbirth,23 Barkin Index of Maternal Functioning,24 Maternal Concerns Questionnaire,25 Maternal Postpartum Quality of Life Questionnaire,26 Rural Postpartum Quality of Life,27 and Postpartum Symptom Checklist.28A total of 24 global recovery PROMs were identified among all included studies. Seventeen PROMs assessing global recovery were identified among the outpatient studies. The Short-Form 36 Health Questionnaire was the most frequently used global recovery PROM among these studies. Seven of the 17 global recovery PROMs were specifically designed for use in the postpartum population. One of these PROMs was a patient-generated item list (Mother-Generated Index)23 Barkin Index of Maternal Functioning,24 and Postpartum Symptom Checklist28) and 4 PROMs were unique to the inpatient studies: Obstetric Quality of Recovery Score–11,29 Parents’ Postnatal Sense of Security Swedish instrument,30 Postpartum Comfort Questionnaire,31 and Recovery From Cesarean Section Scale.32Thirteen PROMs assessing global recovery were identified among the inpatient studies. The Short-Form 36 Health Questionnaire was the most frequently used global recovery PROM among inpatient studies. Seven of these 13 PROMs were specifically designed for use in the postpartum population. Of these 7 PROMs, 3 were also reported in outpatient studies . This is a 50-item questionnaire with scoring on a Likert scale from 1 to 4, with an option of writing additional concerns not listed in the questionnaire. This PROM was developed by a panel of 14 mothers within 1 year of delivery and 3 nurses and subsequently tested among 30 women at 3 days postpartum and 7 days after hospital discharge.33 This PROM has been used in 1 further published study34 included in the literature search.A total of 11 obstetric-specific PROMs were used to evaluate global recovery in the included 573 studies. The median number of domains evaluated by these PROMs was 5 . No PROMs were used to assess outpatient cognition or inpatient surgical complications and scar or wound healing issues.The main finding from this scoping review is that there is heterogeneous use of PROMs to assess postpartum recovery. Most of the included studies that used PROMs assessed psychosocial distress. Similar PROMs were broadly used to assess recovery domains in both the inpatient and outpatient settings, with the exception of the maternal-neonatal bonding, fatigue, and cognition domains, which were featured more within inpatient studies. Measures of global recovery also differed among the outpatient and inpatient studies  group can be used to develop and validate a new PROM.36Defining postpartum outpatient recovery through identification of specific domains and PROMs used is an important first step toward phenotyping postpartum recovery. Having identified recovery PROMs, further work is now needed to determine which of these instruments can best measure individual recovery domains as well as global recovery. This assessment and recommendation can be made through a series of systematic reviews of each recovery domain and psychometric evaluation of existing PROMs, using COSMIN methods.38 In the most recent MBRACE-UK  report, maternal suicide was reported as the fifth most common cause of women’s deaths during pregnancy and was reported as the leading cause of death during the first year after pregnancy.39The exponential increase in numbers of studies over time using PROMs to evaluate domains of outpatient recovery suggests that this aspect of obstetric care is clinically important yet still incompletely defined or understood. The interest in postpartum recovery across a breadth of countries also suggests that research in this area is relevant to women residing in multiple cultures and continents globally. The large number of PROMs available to measure psychological, psychiatric, and psychosocial factors after childbirth is reassuring because psychiatric disease has consistently been reported as a major factor associated with maternal mortality during the past 20 years. The UK Confidential Enquiries into Maternal Deaths report found that psychiatric disorders, and suicide in particular, were the leading cause of maternal deaths.12 evaluation of available recovery outcome measures through this review has helped to identify deficient areas. Although all domains are important, the low number of PROMs within some domains may be associated with the limited treatment options. Problems with breastfeeding, for example, may improve after input from a lactation consultant and pain may respond to pharmacotherapy. However, many of the other domains with smaller numbers of PROMs, such as sleep and fatigue, may have fewer therapeutic options available in the primary health care setting. The domains with fewer PROMs may be considered to be aspects of postpartum recovery that are currently underexplored, which may benefit from research to develop novel and effective interventions.The large number of PROMs available to assess symptoms of incontinence and prolapse may reflect the potential association with quality of life, the benefits of early diagnosis, and options for patient referral to physiotherapy and surgical subspecialties such as urogynecology, which may have resulted in increased popularity of these PROMs among postpartum recovery studies. As previously demonstrated by the paucity of recovery PROMs validated for use after cesarean delivery,11 The lack of use of PROMs to guide obstetric care–related value-based reimbursement may partly be owing to the absence of a robustly validated and reliable PROM for use in this setting. Given the vast global expenditure on peripartum services and use of inpatient resources by parturients, this population seems an obvious choice for implementing payment according to quality of care delivered. Future work should focus on evaluating existing PROMs and developing new measures to assess global outpatient quality of recovery as a marker of care delivered.There is growing interest in applying PROMs to evaluate the performance of individual health care professionals, as a tool to benchmark hospital performance and determine value-based reimbursement for care delivered to patients.17 To our knowledge, no studies have compared PROMs with objective measures of different recovery domains.This scoping review has several limitations. First, we screened only titles and abstracts of fully published articles for validated PROMs, which may have resulted in the exclusion of several validated PROMs. However, we think that this review provides a representative sample of PROMs used to assess recovery after childbirth, as the numbers of included articles and PROMs were substantial. Although the large number of included studies justifies our decision to adopt this approach, we were restricted in terms of granularity of data extracted, as not all full articles were retrieved to determine study and PROM quality. We acknowledge that recovery domain classification of PROMs is subjective. Rather than formulating a separate classification system for inpatient-specific domains, we used the outpatient domains of recovery to facilitate comparison of outpatient and inpatient distribution of PROMs among recovery domains. This approach also allowed us to determine whether an inpatient global recovery PROM could potentially be suitable for use in the outpatient setting. Although author discussion yielded 12 recovery domains, it is possible that different domains would emerge from concept elicitation interviews with key stakeholders such as patients, obstetricians, and nurses. We appreciate that objective measures of recovery  may also be effective at assessing recovery domains. For example, only 2 PROMs assessing breastfeeding were reported in this scoping review, as we excluded objective measures of breastfeeding success such as the LATCH score.Most PROMs identified in this review evaluated a single domain of recovery. This finding emphasizes the need to develop a measure that comprehensively assesses the multiple domains of postpartum recovery. Future research should focus on obtaining clinician and patient input on the symptoms and concerns viewed as most important to assess during recovery. The results of this review can be used to develop a conceptual framework to guide the development of a comprehensive measure of recovery that includes the most important domains. Further research is also needed to evaluate the quality of available PROMs and determine the best tool to measure each domain and global postpartum recovery.