Retinaldehyde Binding Protein 1 (RLBP1)

Retinaldehyde-binding protein 1 is a 36-kD water-soluble protein which carries 11-cis-retinaldehyde or 11-cis-retinal as physiologic ligands. It may be a functional component of the visual cycle. Mutations of this gene have been associated with severe rod-cone dystrophy, Bothnia dystrophy (nonsyndromic autosomal recessive retinitis pigmentosa) and retinitis punctata albescens. CRALBP is not expressed in photoreceptors but is abundant in the retinal pigment epithelium (RPE) and Muller cells of the neuroretina, where it carries 11-cis-retinol and 11-cis-retinaldehyde. When expressed in bacteria, recombinant CRALBP containing the R150Q substitution was less soluble than wildtype recombinant CRALBP. Mutant CRALBP was purified and found to lack the ability to bind 11-cis-retinaldehyde.