Section of Animal Biology, Department of Biology, University of Patras, GR-26500, Patras, Greece.
Chromosome Res. 2011 Oct;19(7):869-82. doi: 10.1007/s10577-011-9242-3. Epub 2011 Oct 7.
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.
通过荧光原位杂交分析了包括三个不同属的 15 种林鼠属啮齿动物中的端粒重复序列：雪兔属、旅鼠属和田鼠属。结果表明，在大多数分析的物种中，除了正常的端粒定位外，端粒序列还以大片段的形式存在于着丝粒区周围。端粒序列块的数量、定位和扩增程度因染色体的核型和形态而异。此外，在某些情况下还描述了非着丝粒区的端粒扩增。这些间插的端粒序列是进化上的现代序列，通过不同的机制迅速在染色体的着丝粒区殖民和扩散，并可能在每个物种中独立地进行。此外，我们在三个物种中对端粒重复序列和卫星 DNA Msat-160（也位于着丝粒区）进行了共定位，并在其中一个物种中克隆了端粒重复序列。最后，我们讨论了这些端粒重复序列在该啮齿动物组中报道的高染色体进化率的可能起源和意义。
