Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
34
pubmed:dateCreated
2002-8-19
pubmed:abstractText
Yeast disruptor of telomeric silencing-1 (DOT1) is involved in gene silencing and in the pachytene checkpoint during meiotic cell cycle. Here we show that the Dot1 protein possesses intrinsic histone methyltransferase (HMT) activity. When compared with Rmt1, another putative yeast HMT, Dot1 shows very distinct substrate specificity. While Rmt1 methylates histone H4, Dot1 targets histone H3. In contrast to Rmt1, which can only modify free histones, Dot1 activity is specific to nucleosomal substrates. This was also confirmed using native chromatin purified from yeast cells. We also demonstrate that, like its mammalian homolog PRMT1, Rmt1 specifically dimethylates an arginine residue at position 3 of histone H4 N-terminal tail. In surprising contrast, methylation by Dot1 occurs in the globular domain of nucleosomal histone H3. Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) analysis suggests that H3 lysine 79 is trimethylated by Dot1. The intrinsic nucleosomal histone H3 methyltransferase activity of Dot1 is certainly a key aspect of its function in gene silencing at telomeres, most likely by directly modulating chromatin structure and Sir protein localization. In agreement with a role in regulating localization of histone deacetylase complexes like SIR, an increase of bulk histone acetylation is detected in dot1- cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
277
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
30421-4
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Disruptor of telomeric silencing-1 is a chromatin-specific histone H3 methyltransferase.
pubmed:affiliation
Laval University Cancer Research Center, Hôtel-Dieu de Québec (CHUQ), 9 McMahon Street, Quebec City, Quebec G1R 2J6, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't