AUTHOR=Peshenko Igor V., Olshevskaya Elena V., Dizhoor Alexander M. TITLE=Interaction of GCAP1 with retinal guanylyl cyclase and calcium: sensitivity to fatty acylation JOURNAL=Frontiers in Molecular Neuroscience VOLUME=5 YEAR=2012 URL=https://www.frontiersin.org/journals/molecular-neuroscience/articles/10.3389/fnmol.2012.00019 DOI=10.3389/fnmol.2012.00019 ISSN=1662-5099 ABSTRACT=
Guanylyl cyclase activating proteins (GCAPs) are calcium/magnesium binding proteins within neuronal calcium sensor proteins group (NCS) of the EF-hand proteins superfamily. GCAPs activate retinal guanylyl cyclase (RetGC) in vertebrate photoreceptors in response to light-dependent fall of the intracellular free Ca2+ concentrations. GCAPs consist of four EF-hand domains and contain N-terminal fatty acylated glycine, which in GCAP1 is required for the normal activation of RetGC. We analyzed the effects of a substitution prohibiting N-myristoylation (Gly2 → Ala) on the ability of the recombinant GCAP1 to co-localize with its target enzyme when heterologously expressed in HEK293 cells. We also compared Ca2+ binding and RetGC-activating properties of the purified non-acylated G2A mutant and C14:0 acylated GCAP1