title: Structures of complete RNA polymerase II and its subcomplex, Rpb4/7.
abstract: We determined the x-ray structure of the RNA polymerase (Pol) II subcomplex Rpb4/7 at 2.3 A resolution, combined it with a previous structure of the 10-subunit polymerase core, and refined an atomic model of the complete 12-subunit Pol II at 3.8-A resolution. Comparison of the complete Pol II structure with structures of the Pol II core and free Rpb4/7 shows that the core-Rpb4/7 interaction goes along with formation of an alpha-helix in the linker region of the largest Pol II subunit and with folding of the conserved Rpb7 tip loop. Details of the core-Rpb4/7 interface explain facilitated Rpb4/7 dissociation in a temperature-sensitive Pol II mutant and specific assembly of Pol I with its Rpb4/7 counterpart, A43/14. The refined atomic model of Pol II serves as the new reference structure for analysis of the transcription mechanism and enables structure solution of complexes of the complete enzyme with additional factors and nucleic acids by molecular replacement.
authors.affiliation: Gene Center, University of Munich (LMU), Department of Chemistry and Biochemistry, Feodor-Lynen-Strasse 25, 81377 Munich, Germany.
authors.forename: Karim-Jean
authors.initials: KJ
authors.lastname: Armache
authors.forename: Simone
authors.initials: S
authors.lastname: Mitterweger
authors.forename: Anton
authors.initials: A
authors.lastname: Meinhart
authors.forename: Patrick
authors.initials: P
authors.lastname: Cramer
mesh_terms: D000595:Amino Acid Sequence; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D015394:Molecular Structure; D011487:Protein Conformation; D012319:RNA Polymerase II / Q000737:chemistry*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry*; D029702:Schizosaccharomyces pombe Proteins / Q000737:chemistry*; D016415:Sequence Alignment
chemical_list: D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; D012319:RNA Polymerase II; C423309:RPB4 protein, S cerevisiae; C496332:Rpb7 protein, S pombe; C499659:rpb4 protein, S pombe