Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Mamm Genome. 1999 Jun;10(6):579-84.

Characterization of a swine chromosome-specific centromeric higher-order repeat.

Author information

  • 1Department of Biochemistry, University of Minnesota, St. Paul, Minnesota 55108, USA.

Abstract

The centromeric region of swine chromosomes is comprised of tandemly repeated, divergent DNA monomer units. Here we report that these divergent DNA monomer sequences are organized into higher-order repeats, analogous to the hierarchical organization of alpha-satellite monomers in human centromeres. In this study, a centromeric cosmid clone was shown to be comprised entirely of a 3.3-kb higher-order repeat, with independent copies of this higher-order repeat more than 99% identical to each other. This higher-order repeat is composed of ten divergent monomer units of approximately 340 bp. The ten monomers are on average 79% identical, and all ten monomers are arranged in the same 5' to 3' orientation. In FISH analysis, a cloned 3.3-kb higher-order repeat hybridized to the centromere of Chromosome (Chr) 9 in metaphase spreads and detected two discrete foci in interphase nuclei, demonstrating that this swine higher-order repeat is chromosome-specific. The Chr 9 centromeric array spanned approximately 2.2 Mb as determined by pulsed-field gel electrophoresis. Moreover, the swine Chr 9 centromere is highly polymorphic, because an EcoRI restriction site polymorphism was detected. Thus, the assembly of divergent satellite sequences into chromosome-specific higher-order repeats appears to be a common organizational feature of both the human and swine centromere and suggests that the evolutionary mechanism(s) that create and maintain higher-order repeats is conserved between their genomes.

PMID:
10341089
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for Springer
    Loading ...
    Write to the Help Desk