Switching the centromeres on and off: epigenetic chromatin alterations provide plasticity in centromere activity stabilizing aberrant dicentric chromosomes.

Content Provider	Semantic Scholar
Author	Sato, Hiroaki Saitoh, Shigeaki
Copyright Year	2013
Abstract	The kinetochore, which forms on a specific chromosomal locus called the centromere, mediates interactions between the chromosome and the spindle during mitosis and meiosis. Abnormal chromosome rearrangements and/or neocentromere formation can cause the presence of multiple centromeres on a single chromosome, which results in chromosome breakage or cell cycle arrest. Analyses of artificial dicentric chromosomes suggested that the activity of the centromere is regulated epigenetically; on some stably maintained dicentric chromosomes, one of the centromeres no longer functions as a platform for kinetochore formation, although the DNA sequence remains intact. Such epigenetic centromere inactivation occurs in cells of various eukaryotes harbouring 'regional centromeres', such as those of maize, fission yeast and humans, suggesting that the position of the active centromere is determined by epigenetic markers on a chromosome rather than the nucleotide sequence. Our recent findings in fission yeast revealed that epigenetic centromere inactivation consists of two steps: disassembly of the kinetochore initiates inactivation and subsequent heterochromatinization prevents revival of the inactivated centromere. Kinetochore disassembly followed by heterochromatinization is also observed in normal senescent human cells. Thus epigenetic centromere inactivation may not only stabilize abnormally generated dicentric chromosomes, but also be part of an intrinsic mechanism regulating cell proliferation.
Starting Page	681
Ending Page	690
Page Count	10
File Format	PDF HTM / HTML
Alternate Webpage(s)	http://www.biochemsoctrans.org/content/ppbiost/41/6/1648.full.pdf
PubMed reference number	24256269v1
Alternate Webpage(s)	https://doi.org/10.1042/BST20130136
DOI	10.1042/bst20130136
Journal	Biochemical Society transactions
Volume Number	41
Issue Number	6
Language	English
Access Restriction	Open
Subject Keyword	Base Sequence Cell Cycle Arrest Cell Proliferation Centromere Chromosome Breakage Chromosomes DNA Sequence Rearrangement Dicentric chromosome Disassembly (action) Kinetochores Meiosis Mitosis Mitotic Cell Cycle Nucleotides Schizosaccharomyces pombe kinetochore assembly study of epigenetics
Content Type	Text
Resource Type	Article