GCAP1 Antibody

Background:

Guanylate cyclase-activating protein is a l Ca(2+)-binding protein that upregulates synthesis of cGMP in photoreceptors. The known mammalian GCAPs are more than 90% similar, consisting of 201 to 205 amino acids, and containing 3 identically conserved Ca(2+)-binding sites. The GUCA1A gene, also termed GCAP1, is transcribed into a single 1.7-kb mRNA species detectable only in the retina. In a 4-generation British family with typical clinical features of autosomal dominant cone dystrophy a tyr99-to-cys mutation) in the GUCA1A gene has been identified. Another family with a pro50-to-leu mutation in GUCA1A demonstrated phenotypic variability ranging from mild photophobia to rod-cone dystrophy. The mutant protein could activate guanylate cyclase 1 (GUCY2D) and displayed similar calcium sensitivity to wildtype protein. However, there was a marked increase in the susceptibility to protease degradation and a reduction in the thermal stability of the pro50-to-leu mutation, which may depress cellular concentration and thereby contribute to retinal cell mortality.