Cryo-EM of RNAP post-terminal complexes bound to RapA+ADP+AlF3 on negatively supercoiled DNA
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ABSTRACT:
SUBMITTER: Seth A Darst
PROVIDER: EMPIAR-12595 | biostudies-other |
REPOSITORIES: biostudies-other
Publications
RapA opens the RNA polymerase clamp to disrupt post-termination complexes and prevent cytotoxic R-loop formation.
Brewer Joshua J JJ Inlow Koe K Mooney Rachel A RA Bosch Barbara B Olinares Paul Dominic B PDB Marcelino Leandro Pimentel LP Chait Brian T BT Landick Robert R Gelles Jeff J Campbell Elizabeth A EA Darst Seth A SA
Nature structural & molecular biology 20250108 4
Following transcript release during intrinsic termination, Escherichia coli RNA polymerase (RNAP) often remains associated with DNA in a post-termination complex (PTC). RNAPs in PTCs are removed from the DNA by the SWI2/SNF2 adenosine triphosphatase (ATPase) RapA. Here we determined PTC structures on negatively supercoiled DNA and with RapA engaged to dislodge the PTC. We found that core RNAP in the PTC can unwind DNA and initiate RNA synthesis but is prone to producing R-loops. Nucleotide bindi ...[more]
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