From pathogens to microbiota: How Drosophila intestinal stem cells react to gut microbes.
The intestine acts as one of the interfaces between an organism and its external environment. As the primary digestive organ, it is constantly exposed to a multitude of stresses as it processes and absorbs nutrients. Among these is the recurring damage induced by ingested pathogenic and commensal microorganisms. Both the bacterial activity and immune response itself can result in the loss of epithelial cells, which subsequently requires replacement. In the Drosophila midgut, this regenerative role is fulfilled by intestinal stem cells (ISCs). Microbes not only trigger cell loss and replacement, but also modify intestinal and whole organism physiology, thus modulating ISC activity. Regulation of ISCs is integrated through a complex network of signaling pathways initiated by other gut cell populations, including enterocytes, enteroblasts, enteroendocrine and visceral muscles cells. The gut also receives signals from circulating immune cells, the hemocytes, to properly respond against infection. This review summarizes the types of gut microbes found in Drosophila, mechanisms for their elimination, and provides an integrated view of the signaling pathways that regulate tissue renewal in the midgut.
['Bonfini|Alessandro|A|', 'Liu|Xi|X|', 'Buchon|Nicolas|N|']
D000818:Animals D000942:Antigens, Bacterial D004331:Drosophila melanogaster D054884:Host-Pathogen Interactions D007413:Intestinal Mucosa D007422:Intestines D064307:Microbiota D012038:Regeneration D015398:Signal Transduction D013234:Stem Cells
Intestinal stem cells Drosophila midgut Epithelium renewal Innate immunity Microbiota and pathogens Regeneration