ATP-binding cassette transporter A1 (ABCA1) (ABCA1)

ATP-binding cassette transporter A1 (ABCA1) is a pivotal membrane protein that mediates the efflux of cellular cholesterol and phospholipids to lipid-poor apolipoprotein A-I (ApoA-I), serving as the rate-limiting step in the formation of high-density lipoprotein (HDL) (UniProt P94184). This mechanism, known as reverse cholesterol transport, is vital for maintaining lipid homeostasis by removing excess cholesterol from peripheral tissues, such as arterial macrophages, and transporting it to the liver for biliary excretion (PubMed: 21856025). Mutations in the ABCA1 gene are the underlying cause of Tangier disease, a rare genetic disorder characterized by extremely low HDL levels and an increased risk of premature coronary artery disease (NCBI Gene ID: 19). In therapeutic development, ABCA1 is targeted to treat atherosclerosis and cardiovascular diseases through pharmacological upregulation, often via Liver X Receptor (LXR) or Peroxisome Proliferator-Activated Receptor (PPAR) agonists (PubMed: 10431241). Additionally, ABCA1 has emerged as a target in neurodegenerative research, as it influences brain lipid metabolism and the clearance of amyloid-beta peptides associated with Alzheimer's disease (PubMed: 25159591). Despite its therapeutic potential, challenges include managing off-target effects like hepatic steatosis and hypertriglyceridemia often associated with systemic LXR activation (PubMed: 17301251).

Other names

ABC1Cholesterol efflux regulatory proteinCERPATP-binding cassette sub-family A member 1HDLDT1Tangier disease protein

Transcriptional upregulation of the ABCA1 gene through the activation of nuclear receptors such as Liver X Receptor (LXR) and Peroxisome Proliferator-Activated Receptor (PPAR), or post-translational stabilization of the ABCA1 protein to enhance the efflux of cellular cholesterol to apolipoprotein A-I acceptors.