ATP11C

ATP11C is a human gene encoding a member of the P4-ATPase family of phospholipid flippases. P4-ATPases use energy from ATP hydrolysis to transport specific phospholipids from the outer to the inner leaflet of cellular membranes, contributing to the asymmetric distribution of lipids that is essential for membrane structure and function. ATP11C acts as the catalytic subunit in a heteromeric flippase complex that typically includes a CDC50 family regulatory subunit, such as CDC50A, which assists in proper trafficking, stability, and activity of the complex.

The ATP11C-containing flippase localizes to the plasma membrane and certain intracellular membranes, where it translocates aminophospholipids, particularly phosphatidylserine and phosphatidylethanolamine. This activity helps maintain lipid asymmetry, supports membrane curvature and vesicle trafficking, and can influence signaling pathways linked to apoptosis and immune cell function.

Expression of ATP11C is widespread, with notable levels in hematopoietic tissues. Its activity is governed by complex formation with CDC50 subunits and by intracellular trafficking; disruptions to the complex can perturb membrane asymmetry and affect cellular processes such as development, survival, and immune cell maturation.

Clinical significance is not tied to a single disease in a straightforward manner, but alterations in ATP11C expression or function have been implicated in studies of hematopoietic cell biology and immune cell development. Related proteins in the same family include ATP11A and ATP11B, which share functional similarities as P4-ATPase flippases.