Influence of proteolytic cleavage of ENaC’s γ subunit upon Na+ and K+ handling

Abstract

The epithelial Na+ channel (ENaC) is activated in vitro by post-translational proteolysis. In vivo, low Na+ or high K+ diets enhance ENaC proteolysis, and proteolysis is hypothesized to contribute to channel activation in these settings. Using a mouse expressing ENaC with disruption of a key proteolytic cleavage site, this study demonstrates that impaired proteolytic activation of ENaC’s γ subunit has little impact upon channel open probability or the ability of mice to adapt to low Na+ or high K+ diets.