Related Experiment Video
Updated: Jun 17, 2026
10:11
Hybrid Ensemble and Single-molecule Assay to Image the Motion of Fully Reconstituted CMG
Published on: July 26, 2024
Human RECQ1 and RECQ4 helicases play distinct roles in DNA replication initiation
Saravanabhavan Thangavel1, Ramiro Mendoza-Maldonado, Erika Tissino
1International Centre for Genetic Engineering and Biotechnology, Padriciano 99, 34149 Trieste, Italy.
Molecular and Cellular Biology
|January 13, 2010
Summary
Human RecQ helicases RECQ1 and RECQ4 are crucial for DNA replication initiation and fork progression. Their specific recruitment to replication origins highlights their distinct roles in the cell cycle and DNA synthesis.
Area of Science:
- Molecular Biology
- Genetics
- Cell Biology
Background:
- RecQ helicases are vital for DNA replication, but their precise in vivo functions remain largely unknown.
- Understanding the roles of human RecQ helicases in DNA replication is critical for comprehending genome stability.
Purpose of the Study:
- To investigate the in vivo association of human RecQ helicases with replication origins.
- To elucidate the specific roles of RECQ1 and RECQ4 in DNA replication initiation and progression.
Main Methods:
- Studied the association of five human RecQ helicases with human replication origins using cell cycle analysis.
- Utilized gene depletion techniques to assess the impact of RECQ1 and RECQ4 on DNA replication.
Main Results:
- RECQ1 and RECQ4 were found to associate with replication origins in a cell cycle-dependent manner.
- RECQ4 is recruited early in G1, while RECQ1 and additional RECQ4 are loaded at the start of S phase.
- Depletion of RECQ1 and RECQ4 reduced origin firing and nascent DNA synthesis, with RECQ4 having a greater effect.
- RECQ1 depletion, but not RECQ4, suppressed replication fork rates.
Conclusions:
- RECQ1 and RECQ4 are integral components of the human DNA replication machinery.
- These helicases play distinct and essential roles in DNA replication initiation and replication fork progression in vivo.
More Related Videos
08:53Strand-Specific Analysis of Proteins at Replicating DNA Strands by Enrichment and Sequencing of Protein-Associated Nascent DNA Method
Published on: May 2, 2025
07:55Detection of Homologous Recombination Intermediates via Proximity Ligation and Quantitative PCR in Saccharomyces cerevisiae
Published on: September 11, 2022
Related Concept Videos
00:55DNA Helicases
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...
01:02The 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...
01:02The 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...
02:31Homologous Recombination
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...
02:31Homologous Recombination
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...
01:29Replication 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...
Many Proteins Orchestrate Replication at the Origin
Eukaryotic replication follows many of the same...