Mechanisms of Bacterial Transcription Termination: All Good Things Must End.

  title={Mechanisms of Bacterial Transcription Termination: All Good Things Must End.},
  author={Ananya Ray-Soni and Michael J. Bellecourt and Robert Landick},
  journal={Annual review of biochemistry},
Transcript termination is essential for accurate gene expression and the removal of RNA polymerase (RNAP) at the ends of transcription units. In bacteria, two mechanisms are responsible for proper transcript termination: intrinsic termination and Rho-dependent termination. Intrinsic termination is mediated by signals directly encoded within the DNA template and nascent RNA, whereas Rho-dependent termination relies upon the adenosine triphosphate-dependent RNA translocase Rho, which binds… 

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Regulation of Transcription Termination of Small RNAs and by Small RNAs: Molecular Mechanisms and Biological Functions

Current knowledge on intrinsic termination of sRNAs and sRNA-mediated Rho-dependent termination of protein coding genes in bacteria is reviewed.

Structural basis for intrinsic transcription termination

Single-particle cryo-electron microscopy structures of Escherichia coli transcription intrinsic termination complexes representing key intermediate states of the event define a structural mechanism for bacterial intrinsic termination and a pathway for RNA release and DNA collapse that is relevant for factor-independent termination by all RNA polymerases.

Processing generates 3′ ends of RNA masking transcription termination events in prokaryotes

Generation of 3′ ends of mRNA by processing is a common phenomenon in prokaryotes as is the case in eukaryotes.

RNA secondary structures regulate three steps of Rho-dependent transcription termination within a bacterial mRNA leader

It is reported that the corA leader also controls two subsequent steps of Rho-dependent termination, which may facilitate regulation of a given coding region by multiple cytoplasmic signals.

Pre-termination Transcription Complex: Structure and Function.

Mechanisms of Bacterial Transcription Termination.

Intrinsic and Rho-dependent termination cooperate for efficient transcription termination at 3’ untranslated regions

Distinct patterns of cooperation between the two modes of termination were observed at the 3’ untranslated regions of the genes to ensure efficient termination and similar mode of operation is demonstrated in Escherichia coli suggesting a likely prevalence of this cooperation across bacteria.

Factor-dependent archaeal transcription termination

The results suggest that the mechanisms used by termination factors in archaea, eukarya, and bacteria to disrupt the TEC may be conserved, and that Eta stimulates release of stalled or arrested TECs.

High-resolution RNA 3′-ends mapping of bacterial Rho-dependent transcripts

It is found that transcripts generated from Rho-dependent termination have precise 3′-ends at steady state, and these termini were localized immediately downstream of energetically stable stem-loop structures, which were not followed by uridine rich sequences.

An allosteric mechanism of Rho-dependent transcription termination

The key structural and functional similarities, which are found between Rho-dependent and intrinsic (Rho-independent) termination pathways, argue that the allosteric mechanism of termination is general and likely to be preserved for all cellular RNAPs throughout evolution.

Unusually long-lived pause required for regulation of a Rho-dependent transcription terminator

An extraordinarily long-lived pause is identified at the site where Rho terminates transcription in the 5′-leader region of the Mg2+ transporter gene mgtA in Salmonella enterica and this data suggest that Rho-dependent termination events that are subject to regulation may require elements distinct from those operating at constitutive RHo-dependent terminators.

Regulation of rho-dependent transcription termination by NusG is specific to the Escherichia coli elongation complex.

It is concluded that NusG modulates Rho-dependent termination by interacting specifically with the RNAP of the E. coli elongation complex to render the complex more susceptible to the termination activity of Rho.

Rho-dependent transcription termination is essential to prevent excessive genome-wide R-loops in Escherichia coli

The results suggest that factor-dependent transcription termination subserves a surveillance function to prevent translation-uncoupled transcription from generating R-loops, which would block replication fork progression and therefore be lethal, and that NusA performs additional essential functions as well in E. coli.

Nonequilibrium mechanism of transcription termination from observations of single RNA polymerase molecules.

The data suggest that intrinsic terminators function by a nonequilibrium process in which terminator effectiveness is determined by the relative rates of nucleotide addition and paused state entry by the transcription complex.

Bacterial transcription terminators: the RNA 3'-end chronicles.

Rho directs widespread termination of intragenic and stable RNA transcription

Changes in the distribution of Escherichia coli RNAP in response to the Rho-specific inhibitor bicyclomycin point to a role of noncoding transcription in E. coli gene regulation that may resemble the ubiquitous nonc coding transcription recently found to play myriad roles in eukaryotic gene regulation.

Transcription Termination: Primary Intermediates and Secondary Adducts*

Analysis of complexes formed between DNA template, nascent RNA, and Escherichia coli RNA polymerase during transcription through the tR2 terminator of bacteriophage λ shows no termination intermediates that withstand dissociation in the time scale appropriate for biochemical studies.

Rho-dependent termination and ATPases in transcript termination.

Termination efficiency at rho-dependent terminators depends on kinetic coupling between RNA polymerase and rho.

Evidence is presented that termination efficiency at a rho-dependent terminator is an inverse function of the rate of elongation of RNA polymerase, and each of the mutant phenotypes can be accounted for by the altered rate of lengthening of the mutants.