Proliferating cell nuclear antigen (PCNA) is required for cell cycle-regulated silent chromatin on replicated and nonreplicated genes
Authors
Miller, AndrewChen, Jiji
Takasuka, Taichi E.
Jacobi, Jennifer L.
Kaufman, Paul D.
Irudayaraj, Joseph M.K.
Kirchmaier, Ann L.
UMass Chan Affiliations
Program in Gene Function and ExpressionDocument Type
Journal ArticlePublication Date
2010-09-04Keywords
AcetylationAntigens, Nuclear
Cell Cycle Proteins
Chromatin
Chromosomes, Fungal
DNA Replication
DNA, Fungal
Gene Silencing
Genetic Loci
Histone Acetyltransferases
Histones
Molecular Chaperones
Mutation
Proliferating Cell Nuclear Antigen
Ribonucleases
S Phase
Saccharomyces cerevisiae
Saccharomyces cerevisiae Proteins
Genetics and Genomics
Metadata
Show full item recordAbstract
In Saccharomyces cerevisiae, silent chromatin is formed at HMR upon the passage through S phase, yet neither the initiation of DNA replication at silencers nor the passage of a replication fork through HMR is required for silencing. Paradoxically, mutations in the DNA replication processivity factor, POL30, disrupt silencing despite this lack of requirement for DNA replication in the establishment of silencing. We tested whether pol30 mutants could establish silencing at either replicated or non-replicated HMR loci during S phase and found that pol30 mutants were defective in establishing silencing at HMR regardless of its replication status. Although previous studies tie the silencing defect of pol30 mutants to the chromatin assembly factors Asf1p and CAF-1, we found pol30 mutants did not exhibit a gross defect in packaging HMR into chromatin. Rather, the pol30 mutants exhibited defects in histone modifications linked to ASF1 and CAF-1-dependent pathways, including SAS-I- and Rtt109p-dependent acetylation events at H4-K16 and H3-K9 (plus H3-K56; Miller, A., Yang, B., Foster, T., and Kirchmaier, A. L. (2008) Genetics 179, 793-809). Additional experiments using FLIM-FRET revealed that Pol30p interacted with SAS-I and Rtt109p in the nuclei of living cells. However, these interactions were disrupted in pol30 mutants with defects linked to ASF1- and CAF-1-dependent pathways. Together, these results imply that Pol30p affects epigenetic processes by influencing the composition of chromosomal histone modifications.Source
J Biol Chem. 2010 Nov 5;285(45):35142-54. Epub 2010 Sep 2. Link to article on publisher's siteDOI
10.1074/jbc.M110.166918Permanent Link to this Item
http://hdl.handle.net/20.500.14038/44072PubMed ID
20813847Related Resources
Link to Article in PubMedae974a485f413a2113503eed53cd6c53
10.1074/jbc.M110.166918