Structural highlights
Function
[RPOC_ECOLI] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.[HAMAP-Rule:MF_01322] [RPOA_ECOLI] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. This subunit plays an important role in subunit assembly since its dimerization is the first step in the sequential assembly of subunits to form the holoenzyme.[HAMAP-Rule:MF_00059] [RPOZ_ECOLI] Promotes RNA polymerase assembly. Latches the N- and C-terminal regions of the beta' subunit thereby facilitating its interaction with the beta and alpha subunits.[HAMAP-Rule:MF_00366] [RPOB_ECOLI] DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates.[HAMAP-Rule:MF_01321]
Publication Abstract from PubMed
Sequence-specific pausing by RNA polymerase (RNAP) during transcription plays crucial and diverse roles in gene expression. In bacteria, RNA structures are thought to fold within the RNA exit channel of the RNAP and can increase pause lifetimes significantly. The biophysical mechanism of pausing is uncertain. We used single-particle cryo-EM to determine structures of paused complexes, including a 3.8-A structure of an RNA hairpin-stabilized, paused RNAP that coordinates RNA folding in the his operon attenuation control region of E. coli. The structures revealed a half-translocated pause state (RNA post-translocated, DNA pre-translocated) that can explain transcriptional pausing and a global conformational change of RNAP that allosterically inhibits trigger loop folding and can explain pause hairpin action. Pause hairpin interactions with the RNAP RNA exit channel suggest how RNAP guides the formation of nascent RNA structures.
RNA Polymerase Accommodates a Pause RNA Hairpin by Global Conformational Rearrangements that Prolong Pausing.,Kang JY, Mishanina TV, Bellecourt MJ, Mooney RA, Darst SA, Landick R Mol Cell. 2018 Mar 1;69(5):802-815.e1. doi: 10.1016/j.molcel.2018.01.018. PMID:29499135[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Kang JY, Mishanina TV, Bellecourt MJ, Mooney RA, Darst SA, Landick R. RNA Polymerase Accommodates a Pause RNA Hairpin by Global Conformational Rearrangements that Prolong Pausing. Mol Cell. 2018 Mar 1;69(5):802-815.e1. doi: 10.1016/j.molcel.2018.01.018. PMID:29499135 doi:http://dx.doi.org/10.1016/j.molcel.2018.01.018
