Acid-sensing ion channel 2 (ASIC2) in the intestine of adult zebrafish

Acid-sensing ion channels (ASICs) in mammals monitor acid sensing and mechanoreception. They have a widespread expression in the central and peripheral nervous system, including the gut. The distribution of ASICs in zebrafish is known only in larvae and at the mRNA level. Here we have investigated the expression and cell distribution of ASIC2 in the gut of adult zebrafish using PCR, Western blot and immunohistochemistry. ASIC2 mRNA was detected in the gut, and a protein consistent with predicted ASIC2 (64 kDa molecular mass) was detected by Western blot. ASIC2 positivity was found in a subpopulation of myenteric neurons in the enteric nervous system, as well in enteroendocrine epithelial cells. These data demonstrate for the first time the occurrence of ASIC2 in the gut of adult zebrafish where it presumably acts as a chemosensor and a mechanosensor.

► Acid-sensing ion channel 2 (ASIC2) is involved in acid sensing and mechanotransduction in mammals, including the gut.
► ASIC2 was examined in the adult zebrafish gut.
► ASIC2 was detected in zebrafish gut at the mRNA and protein level.
► ASIC2 positive intestinal cells were a subpopulation of myenteric neurons and enteroendocrine cells.
► ASIC2 in the zebrafish gut may act as both chemosensor and mechanosensor.