GAK

GAK (cyclin G-associated kinase) is a broadly expressed NAK-family kinase that functions as the mammalian counterpart of auxilin in clathrin-coated vesicle biology. Through a C-terminal J domain, GAK recruits Hsc70 to drive uncoating of clathrin from internalized vesicles, and its kinase domain phosphorylates the AP2 α subunit to influence adaptor function in both endocytosis and trans-Golgi trafficking. GAK localizes to the trans-Golgi network as well as coated pits and vesicles. Variants at the GAK locus are associated with Parkinson disease risk, linking clathrin machinery to α-synuclein handling. Recombinant GAK is used for uncoating, trafficking and kinase-inhibitor studies.