Sif2p interacts with Sir4p amino-terminal domain and antagonizes telomeric silencing in yeast.

Détails

ID Serval
serval:BIB_9179
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Sif2p interacts with Sir4p amino-terminal domain and antagonizes telomeric silencing in yeast.
Périodique
Current Biology
Auteur(s)
Cockell M., Renauld H., Watt P., Gasser S.M.
ISSN
0960-9822
Statut éditorial
Publié
Date de publication
1998
Volume
8
Numéro
13
Pages
787-790
Langue
anglais
Résumé
Several regions of the Saccharomyces cerevisiae genome are subject to position-dependent transcriptional repression mediated by a multi-component nucleosome-binding complex of silent information regulator proteins (Sir2p, Sir3p and Sir4p). These proteins are present in limiting amounts in the nucleus and are targeted to specific chromosomal regions by interaction with sequence-specific DNA-binding factors. Different sites of repression compete for Sir complexes, although it is not known how Sir distribution is regulated. In a screen for factors that interact with Sir4p amino terminus, we have cloned SIF2, which encodes a WD40-repeat-containing factor that disrupts telomeric silencing when overexpressed. In contrast to deletion of SIR4, SIF2 deletion improved telomeric repression, suggesting that under normal conditions Sif2p antagonizes Sir4p function at telomeres. Sif2p overexpression altered the subnuclear localization of Sir4p, but not its protein expression level, suggesting that Sif2p may recruit Sir4p to nontelomeric sites or repression. The sif2 mutant strains were hypersensitive to a range of stress conditions, but did not have decreased viability and did not alter repression in the rDNA. In conclusion, Sif2p resembles the Sir4p regulatory proteins Sir1p and Uth4p in that it competes for the functional assembly of Sir4p at telomeres, yet unlike Sir1p or Uth4p, it does not target Sir4p to either mating-type or rDNA loci.
Mots-clé
Binding, Competitive, Cell Cycle Proteins, Fungal Proteins/antagonists &amp, inhibitors, Fungal Proteins/genetics, Mutation/genetics, Repressor Proteins/metabolism, Repressor Proteins/physiology, Saccharomyces cerevisiae/genetics, Saccharomyces cerevisiae Proteins, Silent Information Regulator Proteins, Saccharomyces cerevisiae, Telomere/physiology
Pubmed
Web of science
Open Access
Oui
Création de la notice
19/11/2007 13:47
Dernière modification de la notice
20/08/2019 15:54
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