title: Proliferating cell nuclear antigen (PCNA) contributes to the high-order structure and stability of heterochromatin in Saccharomyces cerevisiae.
abstract: Heterochromatin plays important roles in the structure, maintenance, and function of the eukaryotic genome. It is associated with special histone modifications and specialized non-histone proteins and assumes a more compact structure than euchromatin. Genes embedded in heterochromatin are generally transcriptionally silent. It was found previously that several mutations of proliferating cell nuclear antigen (PCNA), a DNA replication processivity factor, reduce transcriptional silencing at heterochromatin loci in Saccharomyces cerevisiae. However, the notion that PCNA plays a role in transcriptional silencing was recently questioned because of a potential problem concerning the silencing assays used in prior studies. To determine if PCNA is a bona fide contributor to heterochromatin-mediated transcriptional silencing, we examined the effects of PCNA mutations on heterochromatin structure. We found evidence implicating PCNA in the maintenance of the high-order structure and stability of heterochromatin, which indicates a role of DNA replication in heterochromatin maintenance.
authors.affiliation: Department of Biology, University of Rochester, Rochester, NY, 14627, USA. xin.bi@rochester.edu.
authors.forename: Xin
authors.identifier: 0000-0001-6962-6229
authors.initials: X
authors.lastname: Bi
authors.affiliation: Department of Biology, University of Rochester, Rochester, NY, 14627, USA.
authors.forename: Yue
authors.initials: Y
authors.lastname: Ren
authors.affiliation: Department of Biology, University of Rochester, Rochester, NY, 14627, USA.
authors.forename: Morgan
authors.initials: M
authors.lastname: Kath
mesh_terms: D004260:DNA Repair; D004261:DNA Replication; D020868:Gene Silencing; D006570:Heterochromatin / Q000737:chemistry* / Q000648:ultrastructure; D018809:Proliferating Cell Nuclear Antigen / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000235:genetics*
chemical_list: D006570:Heterochromatin; D018809:Proliferating Cell Nuclear Antigen
keywords: DNA supercoiling; Proliferating cell nuclear antigen (PCNA); heterochromatin; heterochromatin stability; high order structure