The ClC Cl(–) channel CLH-1 mediates HCO(3)(–) efflux from the amphid sheath glia in C. elegans

Cellular function is regulated by the concentration of intracellular and extracellular ions, including pH. Ion channels and transporters that mediate the flux/transport of protons and bicarbonate (HCO(3)(–)) are the chief regulators of pH. In the nervous system, due to their high electrical activity, neurons tend to produce and excrete large amounts of acids. On the contrary, glial cells have been proposed to be key contributors of pH buffering. We published that the Cl(–)/HCO(3)(–) permeable channel CLH-1 mediates intracellular pH buffering of C. elegans Amphid sheath (AMsh) glia at baseline. We show here that, under physiological conditions, clh-1 knock out worms show reduced HCO(3)(– )extrusion from AMsh glia, suggesting that CLH-1 may help prevent cellular alkalinization. This function becomes even more apparent when animals are grown on plates enriched with HCO(3)(–). We speculate that CLH-1 might function as a regulator of extracellular pH.