Related Experiment Video

Updated: Aug 17, 2026

High-throughput Purification of Affinity-tagged Recombinant Proteins
07:44

High-throughput Purification of Affinity-tagged Recombinant Proteins

Published on: August 26, 2012

Control of ColE1 plasmid replication. Intermediates in the binding of RNA I and RNA II

J Tomizawa1

  • 1Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892.

Journal of Molecular Biology
|April 20, 1990
PubMed

Insights

Plasmid ColE1 replication involves small RNA I binding to RNA II, inhibiting DNA primer formation. This interaction proceeds through a series of progressively stable complexes, detailing the molecular mechanism.

Area of Science:

  • Molecular Biology
  • Genetics
  • Biochemistry

Background:

  • Plasmid ColE1 replication is a crucial process in molecular biology.
  • Replication is regulated by a plasmid-encoded small RNA molecule known as RNA I.
  • RNA I functions by binding to RNA II, the precursor to the DNA synthesis primer, thereby inhibiting its formation.

Purpose of the Study:

  • To investigate the step-by-step mechanism of RNA I binding to RNA II.
  • To characterize the intermediate complexes formed during the binding process.
  • To elucidate the structural and kinetic aspects of RNA I-RNA II interaction for ColE1 plasmid replication control.

Main Methods:

  • Kinetic analysis of RNA-RNA binding reactions.
  • Structural studies of RNA complexes.
  • RNase sensitivity assays to identify intermediate complexes.

Main Results:

  • The binding of RNA I to RNA II occurs sequentially, forming complexes of increasing stability.
  • A transient, highly unstable intermediate complex was identified.
  • A more stable, reversible complex with altered RNase sensitivity was characterized.
  • Analysis suggests initial interaction involves complementary loops, preceding stable complex formation.

Conclusions:

  • The binding of RNA I to RNA II is a multi-step process.
  • Each step involves the formation of progressively more stable intermediate complexes.
  • Understanding these intermediates provides insight into the regulation of ColE1 plasmid replication.

More Related Videos

Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events10:59

Artificial RNA Polymerase II Elongation Complexes for Dissecting Co-transcriptional RNA Processing Events

Published on: May 13, 2019

An Assay for Quantifying Protein-RNA Binding in Bacteria07:02

An Assay for Quantifying Protein-RNA Binding in Bacteria

Published on: June 12, 2019

Related Concept Videos

Bacterial RNA Polymerase00:43

Bacterial RNA Polymerase

Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
Eukaryotic RNA Polymerases00:58

Eukaryotic RNA Polymerases

RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
Transcription Initiation01:47

Transcription Initiation

Initiation is the first step of transcription in eukaryotes. Prokaryotic RNA Polymerase (RNAP) can bind to the template DNA and start transcribing. On the other hand, transcription in eukaryotes requires additional proteins, called transcription factors, to first bind to the promoter region in the DNA template. This binding helps recruit the specific RNAP that can assemble on the DNA and start transcription.
The promoters and enhancers and their accessory proteins allow tight regulation of...
Bacterial RNA Polymerase00:43

Bacterial RNA Polymerase

Unlike eukaryotes, bacteria use a single RNA Polymerase (RNAP) to transcribe all genes. The different subunits of bacterial RNAPhave distinct functions. The multisubunit structure of the bacterial RNAP helps the enzyme to maintain catalytic function, facilitate assembly, interact with DNA and RNA, and self-regulate its activity.
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
Eukaryotic RNA Polymerases00:58

Eukaryotic RNA Polymerases

RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
Coordination of Gene Expression Processes in Bacteria01:29

Coordination of Gene Expression Processes in Bacteria

The DNA replication, transcription, and translation processes are intricately coupled in bacteria, allowing efficient gene expression and rapid protein synthesis. While this physical and functional coordination is advantageous, it introduces challenges that bacteria overcome through specific regulatory mechanisms.Coupling of Replication, Transcription, and TranslationThe coupling of replication, transcription, and translation is a hallmark of bacterial gene expression. As the replisome unwinds...