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Title: Regulation of the heterochromatin spreading reaction by trans- acting factors
Heterochromatin is a gene-repressive protein–nucleic acid ultrastructure that is initially nucleated by DNA sequences. However, following nucleation, heterochromatin can then propagate along the chromatin template in a sequence-independent manner in a reaction termed spreading. At the heart of this process are enzymes that deposit chemical information on chromatin, which attracts the factors that execute chromatin compaction and transcriptional or co/post-transcriptional gene silencing. Given that these enzymes deposit guiding chemical information on chromatin they are commonly termed ‘writers’. While the processes of nucleation and central actions of writers have been extensively studied and reviewed, less is understood about how the spreading process is regulated. We discuss how the chromatin substrate is prepared for heterochromatic spreading, and howtrans-acting factors beyond writer enzymes regulate it. We examine mechanisms by whichtrans-acting factors in Suv39, PRC2, SETDB1 and SIR writer systems regulate spreading of the respective heterochromatic marks across chromatin. While these systems are in some cases evolutionarily and mechanistically quite distant, common mechanisms emerge which thesetrans-acting factors exploit to tune the spreading reaction.  more » « less
Award ID(s):
2113319
PAR ID:
10501673
Author(s) / Creator(s):
; ;
Publisher / Repository:
Royal Society
Date Published:
Journal Name:
Open Biology
Volume:
13
Issue:
11
ISSN:
2046-2441
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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