Related Experiment Video
Updated: Jun 25, 2026
07:55
Visualization of DNA Repair Proteins Interaction by Immunofluorescence
Published on: June 26, 2020
[Activation of repair and checkpoint control by double-strand DNA breaks: a cascade of activational protein
Genetika
|February 26, 2009
Abstract:
Molecular mechanisms of activation of DNA repair and checkpoint control by double-strand breaks are considered. They include phosphorylation by protein kinases of repair and checkpoint proteins resulting in their activation, alteration of affinity to other proteins, and alteration of their localization.
Insights
DNA double-strand breaks trigger repair and checkpoint control through protein phosphorylation. This process activates key proteins, altering their interactions and cellular locations for effective DNA damage response.
Area of Science:
- Molecular Biology
- Cellular Biology
- Biochemistry
Background:
- DNA double-strand breaks (DSBs) are severe DNA lesions.
- Efficient repair and checkpoint activation are crucial for genomic stability.
Purpose of the Study:
- To elucidate the molecular mechanisms underlying DNA repair and checkpoint control activation following DSBs.
- To understand how protein kinases mediate these responses.
Main Methods:
- Review of current literature on DNA damage response pathways.
- Analysis of phosphorylation events in DNA repair and checkpoint proteins.
Main Results:
- Protein kinases phosphorylate DNA repair and checkpoint proteins.
- Phosphorylation leads to protein activation.
- Post-translational modifications alter protein-protein interactions and subcellular localization.
Conclusions:
- Phosphorylation is a key regulatory mechanism in DNA double-strand break response.
- Modulation of protein activity and localization is essential for effective DNA repair and cell cycle checkpoint activation.
Related Concept Videos
02:36DNA Damage can Stall the Cell Cycle
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...
02:36DNA Damage Can Stall the Cell Cycle
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...
02:37Restarting 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...
02:04Fixing Double-strand Breaks
The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...
02:04Fixing Double-strand Breaks
The double-stranded structure of DNA has two major advantages. First, it serves as a safe repository of genetic information where one strand serves as the back-up in case the other strand is damaged. Second, the double-helical structure can be wrapped around proteins called histones to form nucleosomes, which can then be tightly wound to form chromosomes. This way, DNA chains up to 2 inches long can be contained within microscopic structures in a cell. A double-stranded break not only damages...
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...