Comparative chromosome mapping of the rRNA genes and telomeric repeats in three Italian pine voles of the Microtus savii s.l. complex (Rodentia, Cricetidae)

摘要: The Microtus (Terricola) savii s. l. complex is a group of five species/subspecies the Italian pine voles, which diverged at different times either with or without chromosomal differentiation. evidence diversification has so far concerned shape sex chromosomes, especially X chromosome. Three taxa group, M. savii, nebrodensis, and tolfetanus have identical karyotypes metacentric chromosomes. chromosomes brachycercus b. niethammericus are, respectively, subtelocentric acrocentric in shape. been long an object conventional karyological studies, but comparative molecular cytogenetic data were completely missing. Therefore, we conducted mapping rRNA genes (rDNA) telomeric repeats three group: niethammericus, each belongs to distinct mitochondrial clade. survey revealed that differentiation clades was accompanied by remarkable changes regard number locations rDNA sites. Thus, nebrodensis high numbers sites, are located centromeric regions of, correspondingly, 18 13 chromosome pairs, whereas shows variable (8–10) heteromorphic sites on both regions. Interstitial (ITS), believed indicate possible breakpoints recurring rearrangements, present largest biarmed nebrodensis. These preliminary results discussed context recent advances phylogeny as well genomic organization rearrangements genus Microtus.