The structure of an RNA polymerase II/general transcription factor TFIIF complex was determined by cryo-electron microscopy and single particle analysis. Density due to TFIIF was not concentrated in one area but rather was widely distributed across the surface of the polymerase. The largest subunit of TFIIF interacted with the dissociable Rpb4/Rpb7 polymerase subunit complex and with the mobile "clamp." The distribution of the second largest subunit of TFIIF was very similar to that previously reported for the sigma subunit in the bacterial RNA polymerase holoenzyme, consisting of a series of globular domains extending along the polymerase active site cleft. This result indicates that the second TFIIF subunit is a true structural homolog of the bacterial sigma factor and reveals an important similarity of the transcription initiation mechanism between bacteria and eukaryotes. The structure of the RNAPII/TFIIF complex suggests a model for the organization of a minimal transcription initiation complex.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Reference||Annotation Extension|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Conditions||Strain||Source||Reference|