Linked Life Data

21896656

Source:http://linkedlifedata.com/resource/pubmed/id/21896656

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
17
pubmed:dateCreated
2011-9-7
pubmed:abstractText
The silent information regulator 2/3/4 (Sir2/3/4) complex is required for gene silencing at the silent mating-type loci and at telomeres in Saccharomyces cerevisiae. Sir3 is closely related to the origin recognition complex 1 subunit and consists of an N-terminal bromo-adjacent homology (BAH) domain and a C-terminal AAA(+) ATPase-like domain. Here, through a combination of structure biology and exhaustive mutagenesis, we identified unusual, silencing-specific features of the AAA(+) domain of Sir3. Structural analysis of the putative nucleotide-binding pocket in this domain reveals a shallow groove that would preclude nucleotide binding. Mutation of this site has little effect on Sir3 function in vivo. In contrast, several surface regions are shown to be necessary for the Sir3 silencing function. Interestingly, the Sir3 AAA(+) domain is shown here to bind chromatin in vitro in a manner sensitive to histone H3K79 methylation. Moreover, an exposed loop on the surface of this Sir3 domain is found to interact with Sir4. In summary, the unique folding of this conserved Sir3 AAA(+) domain generates novel surface regions that mediate Sir3-Sir4 and Sir3-nucleosome interactions, both being required for the proper assembly of heterochromatin in living cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1549-5477
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
25
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1835-46
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Structural basis for the role of the Sir3 AAA+ domain in silencing: interaction with Sir4 and unmethylated histone H3K79.
pubmed:affiliation
Abteilung für Genetik, Zentrum für Medizinische Biotechnologie (ZMB), Universität Duisburg-Essen, D-45141 Essen, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't