7KHB

Escherichia coli RNA polymerase and rrnBP1 promoter open complex

「6WR8」から置き換えられました

7KHB の概要

• エントリーDOI: 10.2210/pdb7khb/pdb
• EMDBエントリー: 21880
• 分子名称: DNA-directed RNA polymerase subunit alpha, ZINC ION, DNA-directed RNA polymerase subunit beta, ... (10 entities in total)
• 機能のキーワード: transcription, transcription-dna complex, transcription/dna
• 由来する生物種: Escherichia coli (strain K12); 詳細
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 500781.96

構造登録者

Shin, Y.,Qayyum, M.Z.,Murakami, K.S. (登録日: 2020-10-20, 公開日: 2020-10-28, 最終更新日: 2025-05-14)

主引用文献

Shin, Y.,Qayyum, M.Z.,Pupov, D.,Esyunina, D.,Kulbachinskiy, A.,Murakami, K.S.
Structural basis of ribosomal RNA transcription regulation.
Nat Commun, 12:528-528, 2021

PubMed Abstract: Ribosomal RNA (rRNA) is most highly expressed in rapidly growing bacteria and is drastically downregulated under stress conditions by the global transcriptional regulator DksA and the alarmone ppGpp. Here, we determined cryo-electron microscopy structures of the Escherichia coli RNA polymerase (RNAP) σ holoenzyme during rRNA promoter recognition with and without DksA/ppGpp. RNAP contacts the UP element using dimerized α subunit carboxyl-terminal domains and scrunches the template DNA with the σ finger and β' lid to select the transcription start site favorable for rapid promoter escape. Promoter binding induces conformational change of σ domain 2 that opens a gate for DNA loading and ejects σ from the RNAP cleft to facilitate open complex formation. DksA/ppGpp binding also opens the DNA loading gate, which is not coupled to σ ejection and impedes open complex formation. These results provide a molecular basis for the exceptionally active rRNA transcription and its vulnerability to DksA/ppGpp.

PubMed: 33483500
DOI: 10.1038/s41467-020-20776-y

実験手法

ELECTRON MICROSCOPY (3.53 Å)