G Kinase Anchoring protein 1 (GKAP1)

GKAP1 is highly similar to the mouse cGMP-dependent protein kinase anchoring protein 42kDa. The mouse protein has been found to localize with the Golgi and recruit cGMP-dependent protein kinase I alpha to the Golgi in mouse testes. It is thought to play a role in germ cell development. Transcript variants encoding different isoforms have been found for this gene.The deduced 366-amino acid protein has a calculated molecular mass of 41.8 kD. Northern blot analysis detected expression in mouse testis only. In situ hybridization showed that Gkap42 was restricted to spermatocytes and early round spermatids. Epitope-tagged Gkap42 concentrated at juxtanuclear regions corresponding to the Golgi complex. Western blot analysis detected a 42-kD endogenous Gkap42 protein in the soluble fraction of mouse testis.