7D7C

CryoEM structure of gp55-dependent RNA polymerase-promoter open complex

7D7C の概要

• エントリーDOI: 10.2210/pdb7d7c/pdb
• EMDBエントリー: 30604
• 分子名称: DNA-directed RNA polymerase subunit alpha, DNA-directed RNA polymerase subunit beta, DNA-directed RNA polymerase subunit beta', ... (8 entities in total)
• 機能のキーワード: transcription, rna polymerase
• 由来する生物種: Escherichia coli; 詳細
• タンパク質・核酸の鎖数: 7
• 化学式量合計: 437384.68

構造登録者

Shi, J.,Wen, A.,Jin, S.,Feng, Y. (登録日: 2020-10-03, 公開日: 2021-01-20, 最終更新日: 2024-03-27)

主引用文献

Shi, J.,Wen, A.,Jin, S.,Gao, B.,Huang, Y.,Feng, Y.
Transcription activation by a sliding clamp.
Nat Commun, 12:1131-1131, 2021

PubMed Abstract: Transcription activation of bacteriophage T4 late genes is accomplished by a transcription activation complex containing RNA polymerase (RNAP), the promoter specificity factor gp55, the coactivator gp33, and a universal component of cellular DNA replication, the sliding clamp gp45. Although genetic and biochemical studies have elucidated many aspects of T4 late gene transcription, no precise structure of the transcription machinery in the process is available. Here, we report the cryo-EM structures of a gp55-dependent RNAP-promoter open complex and an intact gp45-dependent transcription activation complex. The structures reveal the interactions between gp55 and the promoter DNA that mediate the recognition of T4 late promoters. In addition to the σR2 homology domain, gp55 has a helix-loop-helix motif that chaperons the template-strand single-stranded DNA of the transcription bubble. Gp33 contacts both RNAP and the upstream double-stranded DNA. Gp45 encircles the DNA and tethers RNAP to it, supporting the idea that gp45 switches the promoter search from three-dimensional diffusion mode to one-dimensional scanning mode.

PubMed: 33602900
DOI: 10.1038/s41467-021-21392-0

実験手法

ELECTRON MICROSCOPY (3.6 Å)