title: Structure of the tau60/Delta tau91 subcomplex of yeast transcription factor IIIC: insights into preinitiation complex assembly.
abstract: Yeast RNA polymerase III is recruited upon binding of subcomplexes tauA and tauB of transcription factor IIIC (TFIIIC) to the A and B blocks of tRNA gene promoters. The tauB subcomplex consists of subunits tau60, tau91, and tau138. We determined the 3.2 A crystal structure of tau60 bound to a large C-terminal fragment of tau91 (Deltatau91). Deltatau91 protein contains a seven-bladed propeller preceded by an N-terminal extension, whereas tau60 contains a structurally homologous propeller followed by a C-terminal domain with a novel alpha/beta fold. The two propeller domains do not have any detectable DNA binding activity and mediate heterodimer formation that may serve as scaffold for tau138 assembly. We show that the C-terminal tau60 domain interacts with the TATA binding protein (TBP). Recombinant tauB recruits TBP and stimulates TFIIIB-directed transcription on a TATA box containing tRNA gene, implying a combined contribution of tauA and tauB to preinitiation complex formation.
authors.affiliation: European Molecular Biology Laboratory, Grenoble Outstation, B.P. 181, 38042 Grenoble Cedex 9, France.
authors.forename: Anastasia
authors.initials: A
authors.lastname: Mylona
authors.forename: Carlos
authors.initials: C
authors.lastname: Fernández-Tornero
authors.forename: Pierre
authors.initials: P
authors.lastname: Legrand
authors.forename: Melina
authors.initials: M
authors.lastname: Haupt
authors.forename: André
authors.initials: A
authors.lastname: Sentenac
authors.forename: Joël
authors.initials: J
authors.lastname: Acker
authors.forename: Christoph W
authors.initials: CW
authors.lastname: Müller
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D019281:Dimerization; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry; D019474:Transcription Factors, TFIII / Q000737:chemistry* / Q000502:physiology*; D014158:Transcription, Genetic; D000098832:Transcription Factor TFIIIC
chemical_list: D011994:Recombinant Proteins; D019474:Transcription Factors, TFIII; D000098832:Transcription Factor TFIIIC