Molecular cloning and characterization of mouse Gipc3.

GIPC1/GIPC interacts with GTPase-activating protein RGS-GAIP, transmembrane protein M-SemF, receptor tyrosine kinase TrkA, integrin alpha 6A subunit, and TGF beta type III receptor. Kermit, a Xenopus orthologue of human GIPC1, interacts with Frizzled-3 (FZD3) class of WNT receptor. We have recently cloned and characterized human GIPC2 and GIPC3. Here, we identified mouse Gipc3 gene fragments by using bioinformatics, and isolated mouse Gipc3 cDNAs by using cDNA-PCR. Mouse Gipc3 gene encoded a 297-amino-acid protein, showing 86.2% total-amino-acid identity with human GIPC3. In addition to the central PDZ domain, GIPC homologous domain 1 (GH1 domain) and GH2 domain were found to be conserved among mouse Gipc3, Gipc1, Gipc2, and Xenopus Kermit. Mouse Gipc3 gene was found to consist of 6 exons, and exon-intron structure was well conserved between mouse Gipc3 gene and human GIPC3 gene. Mouse Gipc3 mRNA was relatively highly expressed in adult lung, and was also expressed in brain and testis, but was almost undetectable in 7-, 11-, 15, and 17-day whole embryos. This is the first report on molecular cloning and initial characterization of mouse Gipc3.