DNA-directed RNA polymerase II subunit RPB1 / General transcription and DNA repair factor IIH helicase subunit XPD/RAD3 / Transcription elongation factor S-II / DNA-directed RNA polymerase II subunit RPB2 / TATA-box-binding protein / DNA-directed RNA polymerase II subunit RPB3 / DNA-directed RNA polymerase II subunit RPB4 / DNA-directed RNA polymerases I, II, and III subunit RPABC1 / DNA-directed RNA polymerases I, II, and III subunit RPABC2 / DNA-directed RNA polymerases I, II, and III subunit RPABC3 ...DNA-directed RNA polymerase II subunit RPB1 / General transcription and DNA repair factor IIH helicase subunit XPD/RAD3 / Transcription elongation factor S-II / DNA-directed RNA polymerase II subunit RPB2 / TATA-box-binding protein / DNA-directed RNA polymerase II subunit RPB3 / DNA-directed RNA polymerase II subunit RPB4 / DNA-directed RNA polymerases I, II, and III subunit RPABC1 / DNA-directed RNA polymerases I, II, and III subunit RPABC2 / DNA-directed RNA polymerases I, II, and III subunit RPABC3 / DNA-directed RNA polymerases I, II, and III subunit RPABC5 / DNA-directed RNA polymerase II subunit RPB9 / Transcription initiation factor IIB / Transcription initiation factor IIA large subunit / Transcription initiation factor IIA subunit 2 / General transcription and DNA repair factor IIH subunit TFB1 / DNA-directed RNA polymerase II subunit RPB7 / Transcription initiation factor IIE subunit alpha / Transcription initiation factor IIE subunit beta / DNA-directed RNA polymerase II subunit RPB11 / DNA-directed RNA polymerases I, II, and III subunit RPABC4 / Transcription initiation factor IIF subunit alpha / Transcription initiation factor IIF subunit beta / General transcription and DNA repair factor IIH helicase/translocase subunit XPB/SSL2 / General transcription and DNA repair factor IIH subunit TFB2 / General transcription and DNA repair factor IIH subunit SSL1 / General transcription and DNA repair factor IIH subunit TFB4 / General transcription and DNA repair factor IIH subunit TFB5 類似検索 - 構成要素
ジャーナル: Nucleic Acids Res / 年: 2024 タイトル: Transcription start site scanning requires the fungi-specific hydrophobic loop of Tfb3. 著者: Chun Yang / Pratik Basnet / Samah Sharmin / Hui Shen / Craig D Kaplan / Kenji Murakami / 要旨: RNA polymerase II (pol II) initiates transcription from transcription start sites (TSSs) located ∼30-35 bp downstream of the TATA box in metazoans, whereas in the yeast Saccharomyces cerevisiae, ...RNA polymerase II (pol II) initiates transcription from transcription start sites (TSSs) located ∼30-35 bp downstream of the TATA box in metazoans, whereas in the yeast Saccharomyces cerevisiae, pol II scans further downstream TSSs located ∼40-120 bp downstream of the TATA box. Previously, we found that removal of the kinase module TFIIK (Kin28-Ccl1-Tfb3) from TFIIH shifts the TSS in a yeast in vitro system upstream to the location observed in metazoans and that addition of recombinant Tfb3 back to TFIIH-ΔTFIIK restores the downstream TSS usage. Here, we report that this biochemical activity of yeast TFIIK in TSS scanning is attributable to the Tfb3 RING domain at the interface with pol II in the pre-initiation complex (PIC): especially, swapping Tfb3 Pro51-a residue conserved among all fungi-with Ala or Ser as in MAT1, the metazoan homolog of Tfb3, confers an upstream TSS shift in vitro in a similar manner to the removal of TFIIK. Yeast genetic analysis suggests that both Pro51 and Arg64 of Tfb3 are required to maintain the stability of the Tfb3-pol II interface in the PIC. Cryo-electron microscopy analysis of a yeast PIC lacking TFIIK reveals considerable variability in the orientation of TFIIH, which impairs TSS scanning after promoter opening.