Enables retinol binding activity. Involved in several processes, including animal organ development; gluconeogenesis; and negative regulation of cardiac muscle cell proliferation. Acts upstream of or within several processes, including detection of light stimulus involved in visual perception; retinoid metabolic process; and terpenoid transport. Located in extracellular space. Is expressed in several structures, including adipose tissue; brain; genitourinary system; gut; and hindlimb. Human ortholog(s) of this gene implicated in type 2 diabetes mellitus. Orthologous to human RBP4 (retinol binding protein 4). [provided by Alliance of Genome Resources, Apr 2022]