RNA Polymerase Clamp Movement Aids Dissociation from DNA but Is Not Required for RNA Release at Intrinsic Terminators.

ABSTRACT: In bacteria, disassembly of elongating transcription complexes (ECs) can occur at intrinsic terminators in a 2- to 3-nucleotide window after transcription of multiple kilobase pairs of DNA. Intrinsic terminators trigger pausing on weak RNA-DNA hybrids followed by formation of a strong, GC-rich stem-loop in the RNA exit channel of RNA polymerase (RNAP), inactivating nucleotide addition and inducing dissociation of RNA and RNAP from DNA. Although the movements of RNA and DNA during intrinsic termination have been studied extensively leading to multiple models, the effects of RNAP conformational changes remain less well defined. RNAP contains a clamp domain that closes around the nucleic acid scaffold during transcription initiation and can be displaced by either swiveling or opening motions.

SUBMITTER: Bellecourt MJ 

PROVIDER: S-EPMC6402830 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature