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Subunit architecture of general transcription factor TFIIH.

ABSTRACT: 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.

SUBMITTER: Gibbons BJ

PROVIDER: S-EPMC3277522 | biostudies-literature | 2012 Feb

REPOSITORIES: biostudies-literature

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Subunit architecture of general transcription factor TFIIH.

Gibbons Brian J BJ Brignole Edward J EJ Azubel Maia M Murakami Kenji K Voss Neil R NR Bushnell David A DA Asturias Francisco J FJ Kornberg Roger D RD

Proceedings of the National Academy of Sciences of the United States of America 20120120 6

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 th ...[more]

PMID: 22308316

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