ENaC activity is regulated by calpain-2 proteolysis of MARCKS proteins.

ABSTRACT: We previously demonstrated a role for the myristoylated alanine-rich C kinase substrate (MARCKS) to serve as an adaptor protein in the anionic phospholipid phosphate-dependent regulation of the epithelial sodium channel (ENaC). Both MARCKS and ENaC are regulated by proteolysis. Calpains are a family of ubiquitously expressed intracellular Ca²⁺-dependent cysteine proteases involved in signal transduction. Here we examine the role of calpain-2 in regulating MARCKS and ENaC in cultured renal epithelial cells and in the mouse kidney. Using recombinant fusion proteins, we show that MARCKS, but not the ENaC subunits, are a substrate of calpain-2 in the presence of Ca²⁺ Pharmacological inhibition of calpain-2 alters MARCKS protein expression in light-density sucrose gradient

SUBMITTER: Montgomery DS 

PROVIDER: S-EPMC5538800 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature