title: Identification, structure, and functional requirement of the Mediator submodule Med7N/31.
abstract: Mediator is a modular multiprotein complex required for regulated transcription by RNA polymerase (Pol) II. Here, we show that the middle module of the Mediator core contains a submodule of unique structure and function that comprises the N-terminal part of subunit Med7 (Med7N) and the highly conserved subunit Med31 (Soh1). The Med7N/31 submodule shows a conserved novel fold, with two proline-rich stretches in Med7N wrapping around the right-handed four-helix bundle of Med31. In vitro, Med7N/31 is required for activated transcription and can act in trans when added exogenously. In vivo, Med7N/31 has a predominantly positive function on the expression of a specific subset of genes, including genes involved in methionine metabolism and iron transport. Comparative phenotyping and transcriptome profiling identify specific and overlapping functions of different Mediator submodules.
authors.affiliation: Gene Center and Center for Integrated Protein Science Munich (CIPSM), Department of Chemistry and Biochemistry, Ludwig-Maximilians-Universität (LMU) München, Munich, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Koschubs
authors.forename: Martin
authors.initials: M
authors.lastname: Seizl
authors.forename: Laurent
authors.initials: L
authors.lastname: Larivière
authors.forename: Fabian
authors.initials: F
authors.lastname: Kurth
authors.forename: Sonja
authors.initials: S
authors.lastname: Baumli
authors.forename: Dietmar E
authors.initials: DE
authors.lastname: Martin
authors.forename: Patrick
authors.initials: P
authors.lastname: Cramer
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D029721:Drosophila Proteins / Q000737:chemistry* / Q000378:metabolism*; D005816:Genetic Complementation Test; D056892:Mediator Complex; D008958:Models, Molecular; D008969:Molecular Sequence Data; D020836:Protein Structure, Quaternary; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000254:growth & development; D016415:Sequence Alignment; D015534:Trans-Activators / Q000737:chemistry* / Q000378:metabolism*; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D029721:Drosophila Proteins; C526783:Med31 protein, Drosophila; D056892:Mediator Complex; D015534:Trans-Activators; D014157:Transcription Factors