All-trans-retinol (atROL) is stored in hepatic stellate cells (HSCs) in its esterified form. Before esterification takes place, atROL binds to cellular retinol-binding protein 1 (RBP1) (Folli et al. 2001). The resultant complex (RBP1:atROL) serves as a substrate for lecithin retinol acyltransferase (LRAT), the main enzyme responsible for the esterification of atROL. It is thought the binding of RBP1 serves to translocate atROL to the endoplasmic reticulum where LRAT is located.