Themes in Ion Pump Regulation
The Na,K-ATPase is an ion pump present in the plasma membrane. It is of vital importance for cell and body homeostasis and as such is under strict hormonal control. The molecular basis for the acute regulation of Na,K-ATPase is multisite phosphorylation by protein kinases that can alter its behavior. This includes direct effects on the Na,K-ATPase activity, regulation by membrane trafficking, and even dynamic regulation of interaction with regulatory proteins. In shark Na,K-ATPase, the latter includes functional interaction with a small hydrophobic protein of the FXYD protein family, phospholemman-like protein from shark, PLMS. This article summarizes our recent work on the mechanisms involved in the acute regulation of the Na,K-ATPase studied using a plasma membrane preparation from shark salt glands as an epithelial transport model.
multisite phosphorylation protein kinase fxyd proteins plms leucine zipper