Catalyzes the efflux of phospholipids such as sphingomyelin, cholesterol and its oxygenated derivatives like 7beta-hydroxycholesterol and this transport is coupled to hydrolysis of ATP (PubMed:17408620, PubMed:24576892). The lipid efflux is ALB-dependent (PubMed:16702602). Is an active component of the macrophage lipid export complex. Could also be involved in intracellular lipid transport processes. The role in cellular lipid homeostasis may not be limited to macrophages. Prevents cell death by transporting cytotoxic 7beta-hydroxycholesterol (PubMed:17408620). 7beta-hydroxycholesterol(in) + ATP + H2O = 7beta-hydroxycholesterol(out) + ADP + H(+) + phosphate ATP + cholesterol(in) + H2O = ADP + cholesterol(out) + H(+) + phosphate an N-(acyl)-sphingosylphosphocholine(in) + ATP + H2O = ADP + an N-(acyl)-sphingosylphosphocholine(out) + H(+) + phosphate a sphingomyelin(in) + ATP + H2O = a sphingomyelin(out) + ADP + H(+) + phosphate The cholesterol efflux is enhanced by APOA1. Homodimer; disulfide-linked (PubMed:16702602). Homooligomer (PubMed:16702602). May form heterodimers with several heterologous partners of the ABCG subfamily. Forms heterodimers with ABCG4 (PubMed:27228027). Interacts with CAV1; this interaction regulates ABCG1-mediated cholesterol efflux (PubMed:24576892). Predominantly localized in the intracellular compartments mainly associated with the endoplasmic reticulum (ER) and Golgi membranes. Additional isoforms seem to exist. Expressed in several tissues. Expressed in macrophages; expression is increased in macrophages from patients with Tangier disease. Strongly induced in monocyte-derived macrophages during cholesterol influx. Conversely, mRNA and protein expression are suppressed by lipid efflux. Induction is mediated by the liver X receptor/retinoid X receptor (LXR/RXR) pathway. Not induced by bacterial lipopolysaccharides (LPS). Repressed by ZNF202. Palmitoylation at Cys-315 seems important for trafficking from the endoplasmic reticulum. Belongs to the ABC transporter superfamily. ABCG family. Eye pigment precursor importer (TC 3.A.1.204) subfamily. Truncated N-terminus. Truncated N-terminus. Truncated N-terminus. Truncated N-terminus. Truncated N-terminus. Truncated N-terminus. Database for mutations in ABC proteins