Retinol-binding protein 1 (RBP1)

Retinol-binding protein 1 (RBP1), also known as cellular retinol-binding protein 1 (CRBP1), is a cytoplasmic chaperone protein belonging to the fatty acid-binding protein family. It plays a critical role in vitamin A (retinol) homeostasis by binding retinol and retinal with high affinity, protecting them from non-specific oxidation, and facilitating their delivery to specific enzymes for the biosynthesis of retinoic acid or retinyl esters (1.2.1, 1.3.2). RBP1 is widely expressed across various tissues, including the liver, eye, and heart. In the eye, RBP1 is essential for the visual cycle, where it transports all-trans-retinol within the retinal pigment epithelium (1.3.1, 1.5.3). Dysregulation of RBP1 is implicated in several diseases; its loss through epigenetic silencing is a common feature in various cancers, such as breast, ovarian, and lung cancer, leading to impaired retinoic acid signaling and increased tumor malignancy (1.2.4, 1.5.2). Conversely, pharmacological inhibition of RBP1 is being explored as a therapeutic strategy for ocular diseases like Stargardt disease and age-related macular degeneration to slow the accumulation of toxic bis-retinoids (1.3.3, 1.5.3).

Other names

Cellular retinol-binding protein 1CRBP1CRBP-ICRBPRBPCHCRBP1Retinol-binding protein 1, cellular

Competitive inhibition of retinol binding to RBP1 to modulate retinoid flux in the visual cycle and reduce toxic byproduct formation; restoration of RBP1 expression to suppress oncogenic signaling pathways such as PI3K/Akt (1.3.1, 1.3.2, 1.3.3).