First published online September 2, 2003
Journal of Cell Science 116, e1903 (2003)
Copyright © 2003 The Company of Biologists Limited
Centromere activation
Functional centromeres are essential for the correct segregation of
eukaryotic chromosomes during cell division but it is unclear exactly how
centromeric sites are specified in higher eukaryotes. To find out, Hiroshi
Masumoto and co-workers have investigated the reactivation of a functionally
inactive centromere in human cells (see
p. 4021). The
researchers isolated a cell line in which a yeast artificial chromosome (YAC)
containing alphoid DNA - repetitive sequences present in the centromeric
region of human chromosomes - had stably integrated at one end of chromosome
16. In this position, the alphoid YAC had no centromeric activity, as
indicated by the disassembly of centromeric proteins. Treatment of the cells
with a histone deacetylase inhibitor led to reassembly of centromeric proteins
on the alphoid array and minichromosome release. These changes were
accompanied by an increase in histone H3 acetylation and transcription of a
marker gene on the YAC, leading the researchers to conclude that the
alterations in chromatin structure brought about by these processes are
involved in the epigenetic activation of the ectopic alphoid DNA.
Related articles in JCS:
- Epigenetic assembly of centromeric chromatin at ectopic
-satellite sites on human chromosomes
- Megumi Nakano, Yasuhide Okamoto, Jun-ichirou Ohzeki, and Hiroshi Masumoto
JCS 2003 116: 4021-4034.
[Abstract]
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