These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Molecular Cytogenetic Characterization of C-Band-Positive Heterochromatin of the Greater Long-Tailed Hamster (Tscherskia triton, Cricetinae).
    Author: Kamimura E, Uno Y, Yamada K, Nishida C, Matsuda Y.
    Journal: Cytogenet Genome Res; 2022; 162(6):323-333. PubMed ID: 36535261.
    Abstract:
    The greater long-tailed hamster (Tscherskia triton, Cricetinae) has a unique karyotype (2n = 28), containing 11 pairs of acrocentric chromosomes with large C-band-positive centromeric heterochromatin blocks. To understand the origin and evolutionary process of heterochromatin in this species, we isolated novel families of chromosome site-specific highly repetitive DNA sequences from TaqI-digested genomic DNA and then characterized them by chromosome in situ and filter hybridization. The TaqI-families of repetitive sequences were classified into 2 types by their genome organization and chromosomal distribution: the 110-bp repeated sequence organized in large tandem arrays (as satellite DNA), localized to centromeric C-positive heterochromatin of acrocentric autosomes (chromosomes 1-11) and submetacentric X chromosome, and the 405-bp repeated sequence that was composed of 30-32-bp internal repeats, distributed in the pericentromeric region on the short arms of X and Y chromosomes. The repetitive sequences did not cross-hybridize with genomic DNA of any genera of Cricetinae (Mesocricetus, Cricetulus, and Phodopus). These results suggest that the 110-bp and 405-bp repeats rapidly diverged in the lineage of T. triton, evolving in a concerted manner among autosomes and X chromosome and within X and Y chromosomes, respectively. The 110-bp centromeric repeat contained a 17-bp motif in which 9 bases are essential for binding with the centromere-associated protein CENP-B, suggesting the possibility that the 110-bp major satellite DNA carrying the 17-bp motif may have a role in the formation of specified structure and/or function of centromeres in T. triton.
    [Abstract] [Full Text] [Related] [New Search]