A Potassium-Dependent Oxygen Sensing Pathway Regulates Plant Root Hydraulics.
Aerobic organisms survive low oxygen (O2) through activation of diverse molecular, metabolic, and physiological responses. In most plants, root water permeability (in other words, hydraulic conductivity, Lpr) is downregulated under O2 deficiency. Here, we used a quantitative genetics approach in Arabidopsis to clone Hydraulic Conductivity of Root 1 (HCR1), a Raf-like MAPKKK that negatively controls Lpr. HCR1 accumulates and is functional under combined O2 limitation and potassium (K(+)) sufficiency. HCR1 regulates Lpr and hypoxia responsive genes, through the control of RAP2.12, a key transcriptional regulator of the core anaerobic response. A substantial variation of HCR1 in regulating Lpr is observed at the Arabidopsis species level. Thus, by combinatorially integrating two soil signals, K(+) and O2 availability, HCR1 modulates the resilience of plants to multiple flooding scenarios.
['Shahzad|Zaigham|Z|', 'Canut|Matthieu|M|', 'Tournaire-Roux|Colette|C|', 'Martinière|Alexandre|A|', 'Boursiac|Yann|Y|', 'Loudet|Olivier|O|', 'Maurel|Christophe|C|']
D017360:Arabidopsis D029681:Arabidopsis Proteins D004268:DNA-Binding Proteins D018506:Gene Expression Regulation, Plant D020930:MAP Kinase Kinase Kinases D010100:Oxygen D010539:Permeability D018517:Plant Roots D011188:Potassium D014157:Transcription Factors D014867:Water
Raf-like MAPKKK hypoxia anaerobic response environmental stress ethylene responsive transcription factors flooding tolerance plant cell signaling root water transport