Subunit architecture of general transcription factor TFIIH.
Structures of complete 10-subunit yeast TFIIH and of a nested set of subcomplexes, containing 5, 6, and 7 subunits, have been determined by electron microscopy (EM) and 3D reconstruction. Consistency among all the structures establishes the location of the "minimal core" subunits (Ssl1, Tfb1, Tfb2, Tfb4, and Tfb5), and additional densities can be specifically attributed to Rad3, Ssl2, and the TFIIK trimer. These results can be further interpreted by placement of previous X-ray structures into the additional densities to give a preliminary picture of the RNA polymerase II preinitiation complex. In this picture, the key catalytic components of TFIIH, the Ssl2 ATPase/helicase and the Kin28 protein kinase are in proximity to their targets, downstream promoter DNA and the RNA polymerase C-terminal domain.
Department of Structural Biology, Stanford School of Medicine, Stanford, CA 94305, USA.
Brian J
BJ
Gibbons
Edward J
EJ
Brignole
Maia
M
Azubel
Kenji
K
Murakami
Neil R
NR
Voss
David A
DA
Bushnell
Francisco J
FJ
Asturias
Roger D
RD
Kornberg
D002147:Calmodulin / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D008958:Models, Molecular; D046912:Multiprotein Complexes / Q000302:isolation & purification; D021122:Protein Subunits / Q000737:chemistry*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D013194:Staining and Labeling; D051758:Transcription Factor TFIIH / Q000737:chemistry* / Q000302:isolation & purification / Q000648:ultrastructure
D002147:Calmodulin; D046912:Multiprotein Complexes; D021122:Protein Subunits; D051758:Transcription Factor TFIIH