RBP1 (Retinol binding protein 1) belongs to the calycin superfamily and fatty-acid binding protein (FABP) family. RBP1 is the carrier protein involved in the transport of retinol (vitamin A alcohol) from the liver storage site to peripheral tissue. RBP1 can also act as a bridging molecule to recruit histone deacetylases (HDACs), proteins that function as potent regulators of gene expression.