Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
Genetics. 2007 Feb;175(2):513-25. Epub 2006 Dec 6.

The overexpression of a Saccharomyces cerevisiae centromeric histone H3 variant mutant protein leads to a defect in kinetochore biorientation.

Author information

  • 1Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1042, USA.

Abstract

Chromosomes segregate using their kinetochores, the specialized protein structures that are assembled on centromeric DNA and mediate attachment to the mitotic spindle. Because centromeric sequences are not conserved, centromere identity is propagated by an epigenetic mechanism. All eukaryotes contain an essential histone H3 variant (CenH3) that localizes exclusively to centromeres. Because CenH3 is required for kinetochore assembly and is likely to be the epigenetic mark that specifies centromere identity, it is critical to elucidate the mechanisms that assemble and maintain CenH3 exclusively at centromeres. To learn more about the functions and regulation of CenH3, we isolated mutants in the budding yeast CenH3 that are lethal when overexpressed. These CenH3 mutants fall into three unique classes: (I) those that localize to euchromatin but do not alter kinetochore function, (II) those that localize to the centromere and disrupt kinetochore function, and (III) those that no longer target to the centromere but still disrupt chromosome segregation. We found that a class III mutant is specifically defective in the ability of sister kinetochores to biorient and attach to microtubules from opposite spindle poles, indicating that CenH3 mutants defective in kinetochore biorientation can be obtained.

PMID:
17151247
[PubMed - indexed for MEDLINE]
PMCID:
PMC1800591
Free PMC Article

Images from this publication.See all images (5)Free text

F igure  1.—
F igure  2.—
F igure  3.—
F igure  4.—
F igure  5.—
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk