12EC

Half-translocated RNA polymerase elemental paused elongation complex, swiveled (ePEC swiveled)

12EC の概要

• エントリーDOI: 10.2210/pdb12ec/pdb
• EMDBエントリー: 76372
• 分子名称: DNA non-template strand, ZINC ION, DNA template strand, ... (11 entities in total)
• 機能のキーワード: elongation, pausing, pause escape, ppgpp, stringent response, transcription, transcription-dna-rna complex, transcription/dna/rna
• 由来する生物種: Escherichia coli; 詳細
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 441214.82

構造登録者

Mueller, A.U.,Darst, S.A.,Landick, R. (登録日: 2026-03-30, 公開日: 2026-07-01)

主引用文献

Mueller, A.U.,Mooney, R.A.,Engstrom, M.D.,Bao, Y.,Wolfe, M.B.,Sah, B.,Buscher, J.,Saba, J.,Liu, J.,Darst, S.A.,Landick, R.
ppGpp regulates transcription elongation via direct and indirect inputs to RNA polymerase pausing and nucleotide addition.
Biorxiv, 2026

PubMed Abstract: The signaling molecules guanosine 5'-tri/diphosphate 3'-diphosphate, (p)ppGpp, control bacterial protein synthesis rates and cell growth by targeting transcription, translation, NTP synthesis, and other functions. In lineages like , (p)ppGpp produced in response to charged-tRNA deficiency directly targets transcribing RNAP polymerase (RNAP) to match its pace to the pioneering ribosome on the nascent RNA (transcription-translation coupling). However, the mechanism by which (p)ppGpp slows RNAP is poorly defined. (p)ppGpp may allosterically stimulate RNAP pausing, inhibit catalysis, promote backtracking, compete for substrate GTP, inhibit GTP synthesis, or uncouple transcription-translation by inhibiting translation. Using a combination of cryo-EM, biochemical assays, and quantitative nascent elongating transcript sequencing (qNET-seq), we establish that (p)ppGpp allosterically regulates pausing and nucleotide addition via distinct motions of the RNAP swivel module and both competes with and lowers GTP in vivo. (p)ppGpp stimulates swiveling at pause sites to delay escape but may also inhibit counter-swiveling required in every round of nucleotide addition.

PubMed: 42182161
DOI: 10.64898/2026.05.13.724835

実験手法

ELECTRON MICROSCOPY (2.6 Å)