5NSR

Cryo-EM structure of RNA polymerase-sigma54 holo enzyme with promoter DNA closed complex

Summary for 5NSR

• Entry DOI: 10.2210/pdb5nsr/pdb
• EMDB information: 3695
• Descriptor: DNA-directed RNA polymerase subunit alpha, DNA-directed RNA polymerase subunit beta, DNA-directed RNA polymerase subunit beta', ... (7 entities in total)
• Functional Keywords: transcription initiation, rna polymerase, sigma54, transcription
• Biological source: Escherichia coli K-12; More
• Total number of polymer chains: 8
• Total formula weight: 490557.16

Authors

Glyde, R.,Ye, F.Z.,Darbari, V.C.,Zhang, N.,Buck, M.,Zhang, X.D. (deposition date: 2017-04-26, release date: 2017-06-28, Last modification date: 2019-12-11)

Primary citation

Glyde, R.,Ye, F.,Darbari, V.C.,Zhang, N.,Buck, M.,Zhang, X.
Structures of RNA Polymerase Closed and Intermediate Complexes Reveal Mechanisms of DNA Opening and Transcription Initiation.
Mol. Cell, 67:106-116.e4, 2017

PubMed Abstract: Gene transcription is carried out by RNA polymerases (RNAPs). For transcription to occur, the closed promoter complex (RPc), where DNA is double stranded, must isomerize into an open promoter complex (RPo), where the DNA is melted out into a transcription bubble and the single-stranded template DNA is delivered to the RNAP active site. Using a bacterial RNAP containing the alternative σ factor and cryoelectron microscopy, we determined structures of RPc and the activator-bound intermediate complex en route to RPo at 3.8 and 5.8 Å. Our structures show how RNAP-σ interacts with promoter DNA to initiate the DNA distortions required for transcription bubble formation, and how the activator interacts with RPc, leading to significant conformational changes in RNAP and σ that promote RPo formation. We propose that DNA melting is an active process initiated in RPc and that the RNAP conformations of intermediates are significantly different from that of RPc and RPo.

PubMed: 28579332
DOI: 10.1016/j.molcel.2017.05.010

Experimental method

ELECTRON MICROSCOPY (3.8 Å)