CHARACTERIZATION OF THE MURINE POLYCYSTIC KIDNEY-DISEASE (PKD2) GENE

Autosomal dominant polycystic kidney disease (ADPKD) is one of the mos t frequent genetically transmitted disorders among Europeans with an a ttributed frequency of 0.1%. The two most common genetic determinants for ADPKD are the PKD1 and PKD2 genes. In this study we report the gen omic structure and pattern of expression of the Pkd2 gene, the murine homolog of the human PKD2 gene. Pkd2 is localized on mouse Chromosome (Chr) 5 proximal to anchor marker D5Mit175, spans at least 35 kb of th e mouse genome, and consists of 15 exons. Its translation product cons ists of 966 amino acids, and the peptide shows a 95% homology to human polycystin2. Functional domains are particularly well conserved in th e mouse homolog. The expression of mouse polycystin2 in the developing embryo at day 12.5 post conception is localized in mesenchymally deri ved structures. In the adult mouse, the protein is mostly expressed in kidney, which suggests its functional relevance for this organ.