Related Experiment Video
Updated: Oct 1, 2025
11:40
Preparation of the Mgm101 Recombination Protein by MBP-based Tagging Strategy
Published on: June 25, 2013
12.2K
The RecD2 helicase balances RecA activities.
Cristina Ramos1, Rogelio Hernández-Tamayo2,3, María López-Sanz1
1Department of Microbial Biotechnology, Centro Nacional de Biotecnología (CNB-CSIC), Darwin 3, 28049Madrid, Spain.
Nucleic Acids Research
|March 2, 2022
Summary
Bacillus subtilis RecD2 protein, when interacting with RecA, counteracts RecA
Area of Science:
- Molecular Biology
- DNA Replication
- DNA Repair
Background:
- RecD2 family DNA helicases are widespread.
- The specific roles of Bacillus subtilis RecD2 in DNA replication and its interaction with RecA are not fully understood.
- Single-stranded binding protein SsbA may play a role in RecD2 function.
Purpose of the Study:
- To investigate the function of RecD2 during DNA replication.
- To elucidate the interaction between RecD2 and RecA recombinase.
- To understand RecD2's role in overcoming replicative stress.
Main Methods:
- In vivo studies involving recD2 inactivation and mitomycin C treatment.
- In vitro biochemical assays examining RecD2-RecA interactions.
- Analysis of DNA strand-exchange and branch migration.
Main Results:
- RecD2 inhibits replication restart, dependent on SsbA.
- RecD2 counteracts the inhibitory effect of RecA on DNA synthesis.
- RecD2 physically interacts with RecA, modulating its DNA binding and activity.
- recD2 inactivation leads to increased RecA-ssDNA accumulation in vivo.
Conclusions:
- RecD2 plays a crucial role in managing replicative stress by interacting with RecA.
- RecD2 may act as a negative modulator of RecA filament formation by promoting RecA removal from ssDNA.
- These findings clarify the interplay between RecD2, RecA, and SsbA in DNA replication and repair pathways.
Related Concept Videos
02:31Homologous Recombination
54.6K
The basic reaction of homologous recombination (HR) involves two chromatids that contain DNA sequences sharing a significant stretch of identity. One of these sequences uses a strand from another as a template to synthesize DNA in an enzyme-catalyzed reaction. The final product is a novel amalgamation of the two substrates. To ensure an accurate recombination of sequences, HR is restricted to the S and G2 phases of the cell cycle. At these stages, the DNA has been replicated already and the...
54.6K
02:37Restarting Stalled Replication Forks
6.0K
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,...
6.0K
02:53Conservative Site-specific Recombination and Phase Variation
6.2K
Because the DNA segments are cut and reorganized in a direction-specific manner, site-specific recombination has emerged as an efficient genetic engineering technique. Flippase and Cyclization recombinases or Flp and Cre, respectively, are two members of the tyrosine recombinase family derived from bacteriophages, that are used to mediate site-specific DNA insertions, deletions, and targeted expression of proteins in mammalian cell lines.
The recognition sites for Cre recombinase called LoxP...
The recognition sites for Cre recombinase called LoxP...
6.2K
00:55DNA Helicases
22.5K
DNA unwinding helicase enzymes are a type of motor protein. Motor proteins can translocate along filaments or polymers using energy generated from ATP hydrolysis. Helicases are involved in all the important cellular processes where DNA unwinding is required, such as DNA replication, repair, recombination, and transcription. They are present in all living organisms, but vary in their structure, function, and mechanism of action. For example, in prokaryotes, DnaB helicase binds and translocates...
22.5K
03:01The Replisome
35.5K
DNA replication is carried out by a large complex of proteins that act in a coordinated matter to achieve high-fidelity DNA replication. Together this complex is known as the DNA replication machinery or the replisome.
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with...
The synthesis of the leading and lagging strands is a highly coordinated process. To explain this, the “Trombone model” was proposed by Bruce Alberts in 1980. The DNA loop formation starts when a primer is synthesized on the parent lagging strand. The loop grows with...
35.5K
02:37DNA Damage can Stall the Cell Cycle
9.4K
In response to DNA damage, cells can pause the cell cycle to assess and repair the breaks. However, the cell must check the DNA at certain critical stages during the cell cycle. If the cell cycle pauses before DNA replication, the cells will contain twice the amount of DNA. On the other hand, if cells arrest after DNA replication but before mitosis, they will contain four times the normal amount of DNA. With a host of specialized proteins at their disposal,cells must use the right protein at...
9.4K