title: Rapid, independent, and extensive amplification of telomeric repeats in pericentromeric regions in karyotypes of arvicoline rodents.
abstract: The distribution of telomeric repeats was analyzed by fluorescence in situ hybridization in 15 species of arvicoline rodents, included in three different genera: Chionomys, Arvicola, and Microtus. The results demonstrated that in most or the analyzed species, telomeric sequences are present, in addition to normal telomeres localization, as large blocks in pericentromeric regions. The number, localization, and degree of amplification of telomeric sequences blocks varied with the karyotype and the morphology of the chromosomes. Also, in some cases telomeric amplification at non-pericentromeric regions is described. The interstitial telomeric sequences are evolutionary modern and have rapidly colonized and spread in pericentromeric regions of chromosomes by different mechanisms and probably independently in each species. Additionally, we colocalized telomeric repeats and the satellite DNA Msat-160 (also located in pericentromeric regions) in three species and cloned telomeric repeats in one of them. Finally, we discuss about the possible origin and implication of telomeric repeats in the high rate of karyotypic evolution reported for this rodent group.
authors: Section of Animal Biology, Department of Biology, University of Patras, GR-26500, Patras, Greece.
authors: M Th
authors: MT
authors: Rovatsos
authors: J A
authors: JA
authors: Marchal
authors: I
authors: I
authors: Romero-Fernández
authors: F J
authors: FJ
authors: Fernández
authors: E B
authors: EB
authors: Giagia-Athanosopoulou
authors: Antonio
authors: A
authors: Sánchez
mesh_terms: D000818:Animals; D003411:Arvicolinae / Q000145:classification / Q000235:genetics*; D001483:Base Sequence; D002503:Centromere / Q000737:chemistry* / Q000235:genetics; D004276:DNA, Satellite / Q000737:chemistry* / Q000235:genetics; D019143:Evolution, Molecular; D005260:Female; D006570:Heterochromatin / Q000737:chemistry / Q000235:genetics; D017404:In Situ Hybridization, Fluorescence; D059785:Karyotype; D007621:Karyotyping / Q000379:methods*; D008297:Male; D008969:Molecular Sequence Data; D012091:Repetitive Sequences, Nucleic Acid; D016615:Telomere / Q000737:chemistry* / Q000235:genetics
chemical_list: D004276:DNA, Satellite; D006570:Heterochromatin