Human ATP Binding Cassette Transporter A1 (ABCA1) Protein

Background

ABCA1 is a transmembrane protein belonging to the ATP-binding cassette (ABC) transporter family, playing a vital role in lipid metabolism and cellular cholesterol efflux. It facilitates the transport of cholesterol and phospholipids from cells to apolipoproteins, such as ApoA-I, in the plasma, which is a critical step in the formation of high-density lipoprotein (HDL). Structurally, ABCA1 consists of two transmembrane domains and two ATP-binding domains that utilize ATP hydrolysis to drive lipid transport. It is highly expressed in macrophages, hepatocytes, and other cells involved in lipid metabolism. The activity of ABCA1 is essential for maintaining cellular cholesterol homeostasis and preventing lipid accumulation, particularly in macrophages, where its dysfunction can lead to foam cell formation and atherosclerosis. Mutations in the ABCA1 gene are associated with Tangier disease, a rare disorder characterized by very low HDL levels and increased susceptibility to cardiovascular disease. As a key regulator of cholesterol efflux and HDL biogenesis, ABCA1 is a therapeutic target for managing dyslipidemia and cardiovascular risk.