Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

The DNA Replication Fork

The DNA Replication Fork

An organism’s genome needs to be duplicated in an efficient and error-free manner for its growth and survival. The replication fork is a Y-shaped active region where two strands of DNA are separated and replicated continuously. The coupling of DNA unzipping and complementary strand synthesis is a characteristic feature of a replication fork. Organisms with small circular DNA, such as E. coli, often have a single origin of replication; therefore, they have only two replication forks, one in...

The DNA Replication Fork

The DNA Replication Fork

An organism’s genome needs to be duplicated in an efficient and error-free manner for its growth and survival. The replication fork is a Y-shaped active region where two strands of DNA are separated and replicated continuously. The coupling of DNA unzipping and complementary strand synthesis is a characteristic feature of a replication fork. Organisms with small circular DNA, such as E. coli, often have a single origin of replication; therefore, they have only two replication forks, one in...

Restarting Stalled Replication Forks

Restarting Stalled Replication Forks

DNA replication is initiated at sites containing predefined DNA sequences known as origins of replication. DNA is unwound at these sites by the minichromosome maintenance (MCM) helicase and other factors such as Cdc45 and the associated GINS complex.The unwound single strands are protected by replication protein A (RPA) until DNA polymerase starts synthesizing DNA at the 5’ end of the strand in the same direction as the replication fork. To prevent the replication fork from falling apart, a...

Restarting Stalled Replication Forks

Restarting Stalled Replication Forks

DNA replication is initiated at sites containing predefined DNA sequences known as origins of replication. DNA is unwound at these sites by the minichromosome maintenance (MCM) helicase and other factors such as Cdc45 and the associated GINS complex.The unwound single strands are protected by replication protein A (RPA) until DNA polymerase starts synthesizing DNA at the 5’ end of the strand in the same direction as the replication fork. To prevent the replication fork from falling apart, a...

Replication in Eukaryotes

Replication in Eukaryotes

In eukaryotic cells, DNA replication is highly conserved and tightly regulated. Multiple linear chromosomes must be duplicated with high fidelity before cell division, so there are many proteins that fulfill specialized roles in the replication process. Replication occurs in three phases: initiation, elongation, and termination, and ends with two complete sets of chromosomes in the nucleus.
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...

Replication in Eukaryotes

Replication in Eukaryotes

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Transient enhanced cell division by blocking DNA synthesis in <i>Escherichia coli</i>.

Microbiology (Reading, England)·2020

Same author

Imaging of Transcription and Replication in the Bacterial Chromosome with Multicolor Three-Dimensional Superresolution Structured Illumination Microscopy.

Methods in molecular biology (Clifton, N.J.)·2018

Same author

Extrachromosomal Nucleolus-Like Compartmentalization by a Plasmid-Borne Ribosomal RNA Operon and Its Role in Nucleoid Compaction.

Frontiers in microbiology·2018

Same author

Nucleolus-like compartmentalization of the transcription machinery in fast-growing bacterial cells.

Critical reviews in biochemistry and molecular biology·2016

Same author

Thymineless Death Lives On: New Insights into a Classic Phenomenon.

Annual review of microbiology·2015

Same author

Thymineless death, at the origin.

Frontiers in microbiology·2015

Search research articles

Related Experiment Video

Updated: May 12, 2026

Direct Restart of a Replication Fork Stalled by a Head-On RNA Polymerase

Direct Restart of a Replication Fork Stalled by a Head-On RNA Polymerase

Published on: April 29, 2010

Tuning the replication fork progression by the initiation frequency.

Sara González Moreno¹, Carmen Mata Martín, Encarna Ferrera Guillén

¹Departmento de Bioquímica Biología Molecular y Genética, Universidad de Extremadura, 06071, Badajoz, Spain.

Environmental Microbiology

|April 24, 2013

Summary

In Escherichia coli, reduced DNA replication initiation enhances the thermo-resistance of ribonucleotide reductase (RNR101). This improves DNA replication fork progression and suppresses detrimental effects on cell division and viability at high temperatures.

More Related Videos

G2-seq: A High Throughput Sequencing-based Technique for Identifying Late Replicating Regions of the Genome

G2-seq: A High Throughput Sequencing-based Technique for Identifying Late Replicating Regions of the Genome

Published on: March 22, 2018

Inducing a Site Specific Replication Blockage in E. coli Using a Fluorescent Repressor Operator System

Inducing a Site Specific Replication Blockage in E. coli Using a Fluorescent Repressor Operator System

Published on: August 21, 2016

Related Experiment Videos

Last Updated: May 12, 2026

Direct Restart of a Replication Fork Stalled by a Head-On RNA Polymerase

Direct Restart of a Replication Fork Stalled by a Head-On RNA Polymerase

Published on: April 29, 2010

G2-seq: A High Throughput Sequencing-based Technique for Identifying Late Replicating Regions of the Genome

G2-seq: A High Throughput Sequencing-based Technique for Identifying Late Replicating Regions of the Genome

Published on: March 22, 2018

Inducing a Site Specific Replication Blockage in E. coli Using a Fluorescent Repressor Operator System

Inducing a Site Specific Replication Blockage in E. coli Using a Fluorescent Repressor Operator System

Published on: August 21, 2016

Area of Science:

Microbiology
Molecular Biology
Genetics

Background:

Ribonucleotide reductase (RNR) is crucial for DNA synthesis and repair.
The thermo-sensitive RNR101 in Escherichia coli (nrdA101 mutant) exhibits a prolonged thermo-resistant period at 42°C, increasing DNA content.
Impaired replication fork progression is suspected in the nrdA101 mutant.

Purpose of the Study:

To investigate if reduced replication rounds alter the thermo-resistant period of RNR101.
To understand the relationship between DNA initiation frequency and replication fork progression.

Main Methods:

Analysis of oriC/terC ratio and oriC number per cell at 30°C in nrdA101 strains with different oriC alleles.
Assessment of RNR101 thermo-resistance and its effects on cell division, chromosome segregation, and viability at 42°C.

Main Results:

Decreased oriC/terC ratio and oriC number per cell were observed at 30°C with specific oriC alleles in the nrdA101 strain.
These conditions enhanced RNR101 thermo-resistance.
Detrimental effects on cell division, chromosome segregation, and viability at 42°C were suppressed.

Conclusions:

Chromosome initiation deficiency at 30°C enhances replication fork progression in the nrdA101 mutant at 42°C.
Coordination between initiation frequency and replication fork progression is vital for replication systems and cell cycle regulation.