The bacterial multidrug resistance regulator BmrR distorts promoter DNA to activate transcription.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 33293519.
- Also identified by DOI 10.1038/s41467-020-20134-y and PMC identifier 7722741.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The MerR-family proteins represent a unique family of bacteria transcription factors (TFs), which activate transcription in a manner distinct from canonical ones. Here, we report a cryo-EM structure of a B. subtilis transcription activation complex comprising B. subtilis six-subunit (2αββ'ωε) RNA Polymerase (RNAP) core enzyme, σ<sup>A</sup>, a promoter DNA, and the ligand-bound B. subtilis BmrR, a prototype of MerR-family TFs. The structure reveals that RNAP and BmrR recognize the upstream promoter DNA from opposite faces and induce four significant kinks from the -35 element to the -10 element of the promoter DNA in a cooperative manner, which restores otherwise inactive promoter activity by shortening the length of promoter non-optimal -35/-10 spacer. Our structure supports a DNA-distortion and RNAP-non-contact paradigm of transcriptional activation by MerR TFs.
Medical subject headings
- Bacillus subtilis
- Bacterial Proteins
- Drug Resistance, Multiple, Bacterial
- Gene Expression Regulation, Bacterial
- Trans-Activators
- Transcriptional Activation