Guanylate cyclase activator 1C (GUCA1C)

Guanylate cyclase activator 1C (GUCA1C, also known as guanylyl cyclase-activating protein 3 or GCAP3) is a calcium-binding protein found primarily in the retina, especially in photoreceptor cells[1][2][3][4]. It acts as a calcium sensor and modulates guanylate cyclase activity, thereby regulating levels of cyclic GMP during phototransduction, which is crucial for the visual response to light and the proper recovery of photoreceptors after light exposure[1][3]. GUCA1C is part of the recoverin family and contains EF-hand calcium-binding motifs. Mutations or loss-of-function variants in GUCA1C have been linked to primary congenital glaucoma and retinal neurodegenerative diseases such as cone-rod dystrophy and retinitis pigmentosa[2][3]. The protein fine-tunes cone photoreceptor signaling and may differ functionally from its paralogs GCAP1 and GCAP2, contributing to daylight vision and visual sensitivity[1][3]. No drugs are currently known to directly target GUCA1C, but it is relevant as both a candidate disease gene and a modulator of retinal signaling.

Other names

Guanylyl cyclase-activating protein 3GCAP3GCAP 3

Allosteric regulation of membrane-bound guanylate cyclases in a calcium-dependent manner