title: Evidence for ORC-dependent repression of budding yeast genes induced by starvation and other stresses.
abstract: The highly conserved origin recognition complex (ORC) is required for repressing genes in the silent mating type loci of budding yeast. Here we report that at a non-permissive temperature, the temperature-sensitive orc2-1 mutation induces the expression of more than 500 genes, the majority of which are also induced during starvation of wild-type cells. Many genes induced by starvation or by the orc2-1 mutation are also induced by inactivation of proteins required for chromatin-mediated repression of transcription. Genes induced by the orc2-1 mutation, starvation, or inactivation of repressor proteins, map near ORC-binding loci significantly more frequently compared to all genes. Genes repressed by starvation map near ORC-binding sites less frequently compared to all genes, which suggests they have been evolutionarily excluded from regions of repressive chromatin near ORC-binding sites. Deletion of sequences containing ORC-binding sites near the DAL2 and DAL4 genes in the DAL gene cluster, which are induced by either the orc2-1 mutation or by starvation, constitutively activates these genes and abolishes their activation by the orc2-1 mutation. Our findings suggest a role for ORC in the repression of a large number of budding yeast genes induced by starvation or other aspects of a deleterious environment.
authors.affiliation: Department of Cell Stress Biology and Roswell Park Cancer Institute, Buffalo, NY 14263, USA.
authors.forename: Lakshmi
authors.initials: L
authors.lastname: Ramachandran
authors.forename: Debra T
authors.initials: DT
authors.lastname: Burhans
authors.forename: Peter
authors.initials: P
authors.lastname: Laun
authors.forename: Jianxin
authors.initials: J
authors.lastname: Wang
authors.forename: Ping
authors.initials: P
authors.lastname: Liang
authors.forename: Martin
authors.initials: M
authors.lastname: Weinberger
authors.forename: Silke
authors.initials: S
authors.lastname: Wissing
authors.forename: Stefanie
authors.initials: S
authors.lastname: Jarolim
authors.forename: Bernhard
authors.initials: B
authors.lastname: Suter
authors.forename: Frank
authors.initials: F
authors.lastname: Madeo
authors.forename: Michael
authors.initials: M
authors.lastname: Breitenbach
authors.forename: William C
authors.initials: WC
authors.lastname: Burhans
mesh_terms: D017209:Apoptosis; D001665:Binding Sites; D004249:DNA Damage; D015966:Gene Expression Regulation, Fungal; D005810:Multigene Family; D009154:Mutation; D051738:Origin Recognition Complex / Q000235:genetics / Q000502:physiology*; D012097:Repressor Proteins / Q000502:physiology*; D004718:Saccharomycetales / Q000235:genetics* / Q000378:metabolism
chemical_list: D051738:Origin Recognition Complex; D012097:Repressor Proteins