TY - JOUR

T1 - Two conserved modules of Schizosaccharomyces pombe Mediator regulate distinct cellular pathways

AU - Linder, Tomas

AU - Rasmussen, Nina

AU - Samuelsen, Camilla O

AU - Chatzidaki, Emmanouella

AU - Baraznenok, Vera

AU - Beve, Jenny

AU - Henriksen, Peter

AU - Gustafsson, Claes M

AU - Holmberg, Steen

N1 - Keywords: Alleles; Cell Wall; Cyclin-Dependent Kinases; Gene Expression Profiling; Mutation; Phenotype; Protein Subunits; Saccharomyces cerevisiae; Schizosaccharomyces; Schizosaccharomyces pombe Proteins; Trans-Activators

PY - 2008

Y1 - 2008

N2 - Mediator is an evolutionary conserved coregulator complex required for transcription of almost all RNA polymerase II-dependent genes. The Schizosaccharomyces pombe Mediator consists of two dissociable components-a core complex organized into a head and middle domain as well as the Cdk8 regulatory subcomplex. In this work we describe a functional characterization of the S. pombe Mediator. We report the identification of the S. pombe Med20 head subunit and the isolation of ts alleles of the core head subunit encoding med17+. Biochemical analysis of med8(ts), med17(ts), Deltamed18, Deltamed20 and Deltamed27 alleles revealed a stepwise head domain molecular architecture. Phenotypical analysis of Cdk8 and head module alleles including expression profiling classified the Mediator mutant alleles into one of two groups. Cdk8 module mutants flocculate due to overexpression of adhesive cell-surface proteins. Head domain-associated mutants display a hyphal growth phenotype due to defective expression of factors required for cell separation regulated by transcription factor Ace2. Comparison with Saccharomyces cerevisiae Mediator expression data reveals that these functionally distinct modules are conserved between S. pombe and S. cerevisiae.

AB - Mediator is an evolutionary conserved coregulator complex required for transcription of almost all RNA polymerase II-dependent genes. The Schizosaccharomyces pombe Mediator consists of two dissociable components-a core complex organized into a head and middle domain as well as the Cdk8 regulatory subcomplex. In this work we describe a functional characterization of the S. pombe Mediator. We report the identification of the S. pombe Med20 head subunit and the isolation of ts alleles of the core head subunit encoding med17+. Biochemical analysis of med8(ts), med17(ts), Deltamed18, Deltamed20 and Deltamed27 alleles revealed a stepwise head domain molecular architecture. Phenotypical analysis of Cdk8 and head module alleles including expression profiling classified the Mediator mutant alleles into one of two groups. Cdk8 module mutants flocculate due to overexpression of adhesive cell-surface proteins. Head domain-associated mutants display a hyphal growth phenotype due to defective expression of factors required for cell separation regulated by transcription factor Ace2. Comparison with Saccharomyces cerevisiae Mediator expression data reveals that these functionally distinct modules are conserved between S. pombe and S. cerevisiae.

U2 - 10.1093/nar/gkn070

DO - 10.1093/nar/gkn070

M3 - Journal article

C2 - 18310102

VL - 36

SP - 2489

EP - 2504

JO - Nucleic Acids Research

JF - Nucleic Acids Research

SN - 0305-1048

IS - 8

ER -