ABCG1 is a protein that plays a crucial role in the transport of lipids, particularly cholesterol, across cell membranes. It is part of the ATP-binding cassette (ABC) transporter family, which helps move various substances in and out of cells. ABCG1 is primarily expressed in tissues such as the liver and macrophages, where it helps maintain lipid homeostasis. Research has shown that ABCG1 is important for the regulation of cholesterol levels in the body, influencing processes like atherosclerosis and cardiovascular disease. By facilitating the efflux of cholesterol from cells, ABCG1 contributes to the prevention of cholesterol accumulation and related health issues.