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-Structure paper
タイトル | Structural Basis of Transcription: RNA Polymerase Backtracking and Its Reactivation. |
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ジャーナル・号・ページ | Mol Cell, Vol. 75, Issue 2, Page 298-309.e4, Year 2019 |
掲載日 | 2019年7月25日 |
著者 | Mo'men Abdelkareem / Charlotte Saint-André / Maria Takacs / Gabor Papai / Corinne Crucifix / Xieyang Guo / Julio Ortiz / Albert Weixlbaumer / |
PubMed 要旨 | Regulatory sequences or erroneous incorporations during DNA transcription cause RNA polymerase backtracking and inactivation in all kingdoms of life. Reactivation requires RNA transcript cleavage. ...Regulatory sequences or erroneous incorporations during DNA transcription cause RNA polymerase backtracking and inactivation in all kingdoms of life. Reactivation requires RNA transcript cleavage. Essential transcription factors (GreA and GreB, or TFIIS) accelerate this reaction. We report four cryo-EM reconstructions of Escherichia coli RNA polymerase representing the entire reaction pathway: (1) a backtracked complex; a backtracked complex with GreB (2) before and (3) after RNA cleavage; and (4) a reactivated, substrate-bound complex with GreB before RNA extension. Compared with eukaryotes, the backtracked RNA adopts a different conformation. RNA polymerase conformational changes cause distinct GreB states: a fully engaged GreB before cleavage; a disengaged GreB after cleavage; and a dislodged, loosely bound GreB removed from the active site to allow RNA extension. These reconstructions provide insight into the catalytic mechanism and dynamics of RNA cleavage and extension and suggest how GreB targets backtracked complexes without interfering with canonical transcription. |
リンク | Mol Cell / PubMed:31103420 / PubMed Central |
手法 | EM (単粒子) |
解像度 | 3.4 - 3.9 Å |
構造データ | EMDB-4882, PDB-6rh3: EMDB-4885, PDB-6ri7: EMDB-4886, PDB-6ri9: |
化合物 | ChemComp-ZN: ChemComp-CTP: ChemComp-MG: |
由来 |
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キーワード | TRANSCRIPTION / E. coli RNA polymerase / CTP / GreB / Elongation complex / backtracking |