The ATP-binding cassette transporter A1 (ABCA1) protein is a key gatekeeper for regulating intracellular cholesterol transport. It is one member of a large family of genes comprised of cAMP-dependent anion transporter cell membrane proteins. These important proteins regulate reverse cholesterol efflux from cells into the peripheral tissues via apolipoprotein A-1 (apo). ABCA1 in particular has a diverse expression profile and is most highly expressed in macrophages.
