6GFW

Cryo-EM structure of bacterial RNA polymerase-sigma54 holoenzyme initial transcribing complex

Summary for 6GFW

• Entry DOI: 10.2210/pdb6gfw/pdb
• EMDB information: 4397
• Descriptor: DNA-directed RNA polymerase subunit alpha, DNA-directed RNA polymerase subunit beta, DNA-directed RNA polymerase subunit beta', ... (8 entities in total)
• Functional Keywords: transcription initiation, dna opening, transcription bubble, de novo rna synthesis, transcription
• Biological source: Escherichia coli K-12; More
• Total number of polymer chains: 9
• Total formula weight: 484510.28

Authors

Glyde, R.,Ye, F.Z.,Zhang, X.D. (deposition date: 2018-05-02, release date: 2018-07-04, Last modification date: 2024-05-15)

Primary citation

Glyde, R.,Ye, F.,Jovanovic, M.,Kotta-Loizou, I.,Buck, M.,Zhang, X.
Structures of Bacterial RNA Polymerase Complexes Reveal the Mechanism of DNA Loading and Transcription Initiation.
Mol. Cell, 70:1111-1120.e3, 2018

PubMed Abstract: Gene transcription is carried out by multi-subunit RNA polymerases (RNAPs). Transcription initiation is a dynamic multi-step process that involves the opening of the double-stranded DNA to form a transcription bubble and delivery of the template strand deep into the RNAP for RNA synthesis. Applying cryoelectron microscopy to a unique transcription system using σ (σ), the major bacterial variant sigma factor, we capture a new intermediate state at 4.1 Å where promoter DNA is caught at the entrance of the RNAP cleft. Combining with new structures of the open promoter complex and an initial de novo transcribing complex at 3.4 and 3.7 Å, respectively, our studies reveal the dynamics of DNA loading and mechanism of transcription bubble stabilization that involves coordinated, large-scale conformational changes of the universally conserved features within RNAP and DNA. In addition, our studies reveal a novel mechanism of strand separation by σ.

PubMed: 29932903
DOI: 10.1016/j.molcel.2018.05.021

Experimental method

ELECTRON MICROSCOPY (3.7 Å)