Genes for the SMC Family Proteins in a Common Vole Microtus arvalis

Genes for four subfamilies of SMC (structural maintenance of chromosomes) proteins have been isolated from the genome of a common vole Microtus arvalis. The high degree of homology between representatives of each SMC protein subfamily of different classes of organisms has been demonstrated. The full-sized copy of a mammalian gene encoding SMC4 protein has been isolated and analyzed for the first time. The SMC proteins enter into the composition of complexes responsible for cohesion of sister chromatids, formation of mitotic chromosomes, recombination, DNA repair, and regulation of gene expression. We discuss the possible participation of the SMC proteins in inactivation of the X chromosome in mammalian females. Common voles of genus Microtusgroup arvalis serve a unique model for the study of the inactivation process.