8F1J

SigN RNA polymerase early-melted intermediate bound to mismatch DNA fragment dhsU36mm2 (-12A)

8F1J の概要

• エントリーDOI: 10.2210/pdb8f1j/pdb
• EMDBエントリー: 28783 28784 28785
• 分子名称: DNA (36-MER), DNA-directed RNA polymerase subunit alpha, DNA-directed RNA polymerase subunit beta, ... (10 entities in total)
• 機能のキーワード: promoter-bound, initiation, dna melting, transcription bubble nucleation, transcription, transcription-dna complex, transcription/dna
• 由来する生物種: Escherichia coli; 詳細
• タンパク質・核酸の鎖数: 10
• 化学式量合計: 491106.06

構造登録者

Mueller, A.U.,Chen, J.,Darst, S.A. (登録日: 2022-11-05, 公開日: 2023-04-05, 最終更新日: 2024-06-19)

主引用文献

Mueller, A.U.,Chen, J.,Wu, M.,Chiu, C.,Nixon, B.T.,Campbell, E.A.,Darst, S.A.
A general mechanism for transcription bubble nucleation in bacteria.
Proc.Natl.Acad.Sci.USA, 120:e2220874120-e2220874120, 2023

PubMed Abstract: Bacterial transcription initiation requires σ factors for nucleation of the transcription bubble. The canonical housekeeping σ factor, σ, nucleates DNA melting via recognition of conserved bases of the promoter -10 motif, which are unstacked and captured in pockets of σ. By contrast, the mechanism of transcription bubble nucleation and formation during the unrelated σ-mediated transcription initiation is poorly understood. Herein, we combine structural and biochemical approaches to establish that σ, like σ, captures a flipped, unstacked base in a pocket formed between its N-terminal region I (RI) and extra-long helix features. Strikingly, RI inserts into the nascent bubble to stabilize the nucleated bubble prior to engagement of the obligate ATPase activator. Our data suggest a general paradigm of transcription initiation that requires σ factors to nucleate an early melted intermediate prior to productive RNA synthesis.

PubMed: 36972428
DOI: 10.1073/pnas.2220874120

実験手法

ELECTRON MICROSCOPY (2.6 Å)