Calcium Binding Protein 2 (CABP2)

CABP2 belongs to a subfamily of calcium binding proteins, which share similarity to calmodulin. Expression of this gene is retina-specific. The specific function of this gene is unknown. Alternatively spliced transcript variants encoding different isoforms have been identified.CABP2 shares 72% similarity with CABP1 and 56% similarity with calmodulin. Human CABP2 also shares 91 to 98% similarity with the bovine and mouse homologs. Northern blot analysis detected weak expression of 1.5- and 1.3-kb transcripts only in retina. RT-PCR of several mouse tissues detected expression only in retina.CABP2 also inhibited G protein-coupled receptor kinase-5 (GRK5)-mediated phosphorylation of rhodopsin, although its affinity for GRK5 was lower than that shown by CABP1.