Microbial RNAs Pressure Piezo1 to Respond.

Area of Science:

• Gastroenterology
• Molecular Biology
• Microbiology

Background:

• Serotonin production by enterochromaffin cells (ECs) is crucial for gut function but is known to be influenced by the gut microbiota.
• The precise molecular mechanisms by which microbiota regulate EC serotonin production remain largely unknown.

Purpose of the Study:

• To elucidate the mechanism by which intestinal microbiota influence serotonin production in ECs.
• To investigate the role of the Piezo1 channel in mediating this microbiota-EC interaction.

Main Methods:

• Utilized mouse models with specific gene deletions (Piezo1 in ECs).
• Employed techniques to detect single-strand RNA (ssRNA) and measure serotonin levels.
• Assessed physiological outcomes including bone formation, peristalsis, and colitis susceptibility.

Main Results:

• Demonstrated that Piezo1 channels in ECs directly sense ssRNA derived from intestinal microbiota.
• Showed that ssRNA sensing via Piezo1 promotes serotonin production in ECs.
• Found that deletion of Piezo1 in the intestinal epithelium leads to increased bone formation, reduced peristalsis, and protection from colitis due to decreased serotonin.

Conclusions:

• Piezo1 acts as a critical sensor for microbial ssRNA in ECs, linking gut microbiota to host serotonin levels.
• This mechanism highlights a novel pathway influencing gut homeostasis, bone metabolism, and inflammatory responses.
• Targeting Piezo1-mediated signaling may offer therapeutic strategies for conditions associated with altered serotonin levels or gut dysbiosis.