ISOLATION AND CHARACTERIZATION OF THE GENE CODING FOR MURINE HIGH-MOBILITY-GROUP PROTEIN HMGI-C

The HMGI-C protein is a nuclear factor expressed in human and rodent n eoplastic cells which has been shown to be involved in the process of cell transformation. We have previously isolated the cDNA encoding mur ine HMGI-C and now we report the cloning and analysis of the mouse Hmg i-c gene. The gene is at least 50 kb long, contains five exons, and ea ch of the three DNA-binding domains is encoded by a different exon, Th e location of exon-intron junctions was determined and shown to follow the GT-AG rule. The sequence revealed that the overall organization i s similar to the gene encoding human HMGI(Y), the other member of the HMGI family, suggesting that HMGI genes probably evolved through gene duplication and exon shuffling events from an ancestral gene. A highly homologous pseudogene is also present in the mouse genome. Our result s on Hmgi-c structure provide basic information to carry out further s tudies on the regulation of its expression.