Oscillatory transepithelial H(+) flux regulates a rhythmic behavior in C. elegans.

ABSTRACT: In C. elegans, rhythmic defecation is timed by oscillatory Ca(2+) signaling in the intestine [1-5]. Here, by using fluorescent biosensors in live, unrestrained worms, we show that intestinal pH also oscillates during defecation and that transepithelial proton movement is essential for defecation signaling. The intestinal cytoplasm is acidified by proton influx from the lumen during defecation. Acidification is predicted to trigger Na(+)/H(+) exchange activity and subsequent proton efflux. The Na(+)/H(+) exchanger NHX-7 (PBO-4) extrudes protons across the basolateral membrane and is necessary for both acute acidification of the pseudocoelom and for strong contractions of the posterior body wall muscles during defecation. This suggests that secreted protons transmit a signal between the inte

SUBMITTER: Pfeiffer J 

PROVIDER: S-EPMC2350219 | biostudies-literature | 2008 Feb

REPOSITORIES: biostudies-literature