Reorganization of the X chromosome in voles of the genus Microtus

• Published in: Cytogenetic and Genome Research Vol. 99; no. 1-4; pp. 323 - 329
• Main Authors: Rubtsov, N.B., Rubtsova, N.V., Anopriyenko, O.V., Karamysheva, T.V., Shevchenko, A.I., Mazurok, N.A., Nesterova, T.B., Zakian, S.M.
• Format: Journal Article
• Language: English
• Published: Basel, Switzerland S. Karger AG 01.01.2002
• Subjects: Animals; Arvicolinae - genetics; Chromosome Banding; Chromosome Mapping; DNA Probes; Evolution, Molecular; In Situ Hybridization, Fluorescence - methods; Microtus; Repetitive Sequences, Nucleic Acid - genetics; Sex chromosome organization; Species Specificity; X Chromosome - genetics
• ISBN: 9783805576376; 3805576374
• ISSN: 1424-8581; 1424-859X
• DOI: 10.1159/000071611

Comparative chromosomal analysis is a powerful tool in the investigation of the mechanisms of chromosomal evolution. The accuracy of the analysis depends on the availability of region-specific markers to follow the fate of the particular chromosomal region through the evolution of species. We have assigned 12 unique sequences to the euchromatic part of the vole X chromosome, which serve as reliable markers of chromosomal segments. Together with region-specific libraries and GTG banding, these markers allow us to delineate the homologous regions of the X chromosomes in five species of the genus Microtus. We found that X chromosomes of these species differ by numerous rearrangements and all rearrangements are clustered at specific breakpoints. Moreover, these breakpoints were found to colocalise with repetitive and/or duplicated DNA sequences. We suggest that clusters of repeated and/or duplicated DNA sequences have played a crucial role in the formation of rearrangement hot spots during evolution of the X chromosome in the subgenus Microtus.