title: A chimeric subunit of yeast transcription factor IIIC forms a subcomplex with tau95.
abstract: The multisubunit yeast transcription factor IIIC (TFIIIC) is a multifunctional protein required for promoter recognition, transcription factor IIIB recruitment, and chromatin antirepression. We report the isolation and characterization of TFC7, an essential gene encoding the 55-kDa polypeptide, tau55, present in affinity-purified TFIIIC. tau55 is a chimeric protein generated by an ancient chromosomal rearrangement. Its C-terminal half is essential for cell viability and sufficient to ensure TFIIIC function in DNA binding and transcription assays. The N-terminal half is nonessential and highly similar to a putative yeast protein encoded on another chromosome and to a cyanobacterial protein of unknown function. Partial deletions of the N-terminal domain impaired tau55 function at a high temperature or in media containing glycerol or ethanol, suggesting a link between PolIII transcription and metabolic pathways. Interestingly, tau55 was found, together with TFIIIC subunit tau95, in a protein complex which was distinct from TFIIIC and which may play a role in the regulation of PolIII transcription, possibly in relation to cell metabolism.
authors.affiliation: Service de Biochimie et de Génétique Moléculaire, CEA/Saclay, F-91191 Gif-sur-Yvette Cedex, France.
authors.forename: N
authors.initials: N
authors.lastname: Manaud
authors.forename: R
authors.initials: R
authors.lastname: Arrebola
authors.forename: B
authors.initials: B
authors.lastname: Buffin-Meyer
authors.forename: O
authors.initials: O
authors.lastname: Lefebvre
authors.forename: H
authors.initials: H
authors.lastname: Voss
authors.forename: M
authors.initials: M
authors.lastname: Riva
authors.forename: C
authors.initials: C
authors.lastname: Conesa
authors.forename: A
authors.initials: A
authors.lastname: Sentenac
mesh_terms: D000595:Amino Acid Sequence; D004258:DNA Polymerase III / Q000235:genetics; D004271:DNA, Fungal / Q000302:isolation & purification / Q000378:metabolism; D015321:Gene Rearrangement; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016366:Open Reading Frames; D011487:Protein Conformation; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000302:isolation & purification; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D017384:Sequence Deletion; D014157:Transcription Factors / Q000235:genetics*; D019474:Transcription Factors, TFIII; D014158:Transcription, Genetic; D000098832:Transcription Factor TFIIIC
chemical_list: D004271:DNA, Fungal; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; C112471:TFC1 protein, S cerevisiae; D014157:Transcription Factors; D019474:Transcription Factors, TFIII; D000098832:Transcription Factor TFIIIC; D004258:DNA Polymerase III