Format

Send to

Choose Destination
See comment in PubMed Commons below
FASEB J. 1999 Dec;13 Suppl 2:S216-20.

The mammalian centromere: structural domains and the attenuation of chromatin modeling.

Author information

1
Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030, USA.

Abstract

The centromere-kinetochore complex can be divided into distinct domains based on structure and function. Previous work has used CREST auto-antibodies with various microscopic techniques to map the locations of proteins within the centromere-kinetochore complex and to analyze the maturation of prekinetochores before mitosis. Here we have focused on the centromere-specific histone Centromere Protein (CENP)-A and its spatial relationship to other histones and histone modifications found in condensed chromatin. We demonstrate that the phosphorylation of histone H3 is essentially excluded from a specific region of centromeric chromatin, defined by the presence of CENP-A. Interspersion of CENP-B with phosphorylated H3 in the inner centromere indicates that the exclusion of H3 modification is not a general property of alpha-satellite DNA. We also demonstrate that these regions are functionally distinct by fragmenting mitotic chromatin into motile centromere-kinetochore fragments that contain CENP-A with little or no phosphorylated H3 and nonmotile fragments that contain exclusively phosphorylated H3. The sequence of CENP-A diverges from H3 in a number of key residues involved in chromosome condensation and in transcription, potentially allowing a more specialized chromatin structure within centromeric heterochromatin, on which kinetochore plates may nucleate and mature. This specialized centromere subdomain would be predicted to have a very tight and static nucleosome structure as a result of the absence of H3 phosphorylation and acetylation.

PMID:
10619130
[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Support Center