Real-Time Single-Molecule Studies of RNA Polymerase-Promoter Open Complex Formation Reveal Substantial Heterogeneity Along the Promoter-Opening Pathway.

ABSTRACT: The expression of most bacterial genes commences with the binding of RNA polymerase (RNAP)-σ⁷⁰ holoenzyme to the promoter DNA. This initial RNAP-promoter closed complex undergoes a series of conformational changes, including the formation of a transcription bubble on the promoter and the loading of template DNA strand into the RNAP active site; these changes lead to the catalytically active open complex (RP_O) state. Recent cryo-electron microscopy studies have provided detailed structural insight on the RP_O and putative intermediates on its formation pathway. Here, we employ single-molecule fluorescence microscopy to interrogate the conformational dynamics and reaction kinetics during real-time RP_O formation on a consensus lac promoter. We find t

SUBMITTER: Malinen AM 

PROVIDER: S-EPMC8783055 | biostudies-literature | 2022 Jan

REPOSITORIES: biostudies-literature