TY - JOUR
T1 - Mutational analysis of the Sir3 BAH domain reveals multiple points of interaction with nucleosomes
AU - Sampath, Vinaya
AU - Yuan, Peihua
AU - Wang, Isabel X.
AU - Prugar, Evelyn
AU - van Leeuwen, Fred
AU - Sternglanz, Rolf
PY - 2009
Y1 - 2009
N2 - Sir3, a component of the transcriptional silencing complex in the yeast Saccharomyces cerevisiae, has an N-terminal BAH domain that is crucial for the protein's silencing function. Previous work has shown that the N-terminal alanine residue of Sir3 (Ala2) and its acetylation play an important role in silencing. Here we show that the silencing defects of Sir3 Ala2 mutants can be suppressed by mutations in histones H3 and H4, specifically, by H3 D77N and H4 H75Y mutations. Additionally, a mutational analysis demonstrates that three separate regions of the Sir3 BAH domain are important for its role in silencing. Many of these BAH mutations also can be suppressed by the H3 D77N and H4 H75Y mutations. In agreement with the results of others, in vitro experiments show that the Sir3 BAH domain can interact with partially purified nucleosomes. The silencing-defective BAH mutants are defective for this interaction. These results, together with the previously characterized interaction between the C-terminal region of Sir3 and the histone H3/H4 tails, suggest that Sir3 utilizes multiple domains to interact with nucleosomes. Copyright © 2009, American Society for Microbiology. All Rights Reserved.
AB - Sir3, a component of the transcriptional silencing complex in the yeast Saccharomyces cerevisiae, has an N-terminal BAH domain that is crucial for the protein's silencing function. Previous work has shown that the N-terminal alanine residue of Sir3 (Ala2) and its acetylation play an important role in silencing. Here we show that the silencing defects of Sir3 Ala2 mutants can be suppressed by mutations in histones H3 and H4, specifically, by H3 D77N and H4 H75Y mutations. Additionally, a mutational analysis demonstrates that three separate regions of the Sir3 BAH domain are important for its role in silencing. Many of these BAH mutations also can be suppressed by the H3 D77N and H4 H75Y mutations. In agreement with the results of others, in vitro experiments show that the Sir3 BAH domain can interact with partially purified nucleosomes. The silencing-defective BAH mutants are defective for this interaction. These results, together with the previously characterized interaction between the C-terminal region of Sir3 and the histone H3/H4 tails, suggest that Sir3 utilizes multiple domains to interact with nucleosomes. Copyright © 2009, American Society for Microbiology. All Rights Reserved.
UR - https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=66349093144&origin=inward
UR - https://www.ncbi.nlm.nih.gov/pubmed/19273586
U2 - https://doi.org/10.1128/MCB.01682-08
DO - https://doi.org/10.1128/MCB.01682-08
M3 - Article
C2 - 19273586
SN - 0270-7306
VL - 29
SP - 2532
EP - 2545
JO - Molecular and Cellular Biology
JF - Molecular and Cellular Biology
IS - 10
ER -