MARCKS protein

MARCKS proteins (myristoylated alanine-rich C-kinase substrate) play important roles in cell shape, cell motility, secretion, transmembrane transport, and regulation of the cell cycle. Recently, MARCKS has been implicated in the exocytosis of a number of vesicles and granules such as mucin and chromaffin.

They are acidic proteins with high proportions of alanine, glycine, proline, and glutamic acid. They are membrane-bound through a lipid anchor at the N-terminus, and a polybasic domain in the middle. They are regulated by Ca2+/calmodulin and protein kinase C. In their unphosphorylated form, they bind to actin filaments, causing them to crosslink, and sequester acidic membrane phospholipids such as PIP2.