RBP7 Gene - Retinol Binding Protein 7: Function, Expression, and Clinical Significance

RBP7 (Retinol Binding Protein 7) encodes the cellular retinoic acid binding protein 2 (CRABP2), a member of the fatty acid-binding protein (FABP) family. CRABP2 binds retinoic acid (RA) with high affinity and facilitates its transport to the nucleus, where RA activates retinoic acid receptors (RARs) to regulate gene transcription. The protein plays a critical role in retinoid signaling, cell differentiation, proliferation, and lipid metabolism. RBP7 is expressed in various tissues, including skin, adipose tissue, and the reproductive system.

Tissue Expression

Cell Line Expression

Hotspot Mutations

Mutation functional classification

• Retinoic acid signaling pathway (Reactome: R-HSA-5362768)

• Retinoid metabolism and transport (Reactome: R-HSA-975634)

• Gene expression (transcription) by retinoic acid receptors (KEGG: hsa03320)

CRABP2 (encoded by RBP7) is a 138-amino-acid protein (15.6 kDa) that belongs to the intracellular lipid-binding protein family. It contains a beta-barrel structure that forms a ligand-binding pocket specific for all-trans-retinoic acid and 9-cis-retinoic acid. Upon RA binding, CRABP2 undergoes a conformational change that exposes a nuclear localization signal, enabling translocation to the nucleus where it delivers RA to RAR/RXR heterodimers. This process is essential for RA-mediated transcriptional regulation of genes involved in cell cycle control, differentiation, and apoptosis. CRABP2 also interacts with fatty acids and may modulate lipid metabolism independently of retinoid signaling.