C-terminal kinase associated domain 1 (KA1), a phospholipid binding domain, of Kcc4p and similar proteins
This subfamily is composed of three Saccharomyces cerevisiae proteins, Kcc4p, Gin4p, and Hsl1p, as well as similar serine/threonine protein kinases (STKs). They catalyze the transfer of the gamma-phosphoryl group from ATP to S/T residues on protein substrates. Kcc4p, Gin4p, and Hsl1p are septin-associated proteins that are involved in septin organization and in the yeast morphogenesis checkpoint coordinating the cell cycle with bud formation. They negatively regulate the Wee1-related kinase Swe1, which phosphorylates the cyclin-dependent kinase Cdc28, and is involved in regulating the entry of cells into mitosis. Kcc4p, Gin4p, and Hsl1p localize in the bud neck in a septin-dependent manner and display distinct but partially overlapping functions. They contain an N-terminal catalytic kinase domain and a C-terminal KA1 domain. The KA1 domain of Kcc4p, Gin4p, and Hsl1p binds acidic phospholipids including phosphatidylserine (PtdSer) and is required for bud neck localization.
Jiyao W et al.(2023). "The conserved domain database in 2023.",