Homologous Recombination
Homologous Recombination - Related Videos
02:31
Homologous Recombination
0 Views •
2020
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...
02:31
Homologous Recombination
0 Views •
2023
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...
14:23
Recombineering Homologous Recombination Constructs in Drosophila
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Cited by 9 •
2013
Homologous recombination techniques greatly advance Drosophila genetics by enabling the creation of molecularly precise mutations. The recent adoption of recombineering allows one to manipulate large pieces of DNA and transform them into Drosophila6. The methods presented here combine these techniques to rapidly generate large homologous recombination vectors.
04:14
Generation of Antibiotic-Marked Mutants in Cyanobacteria via Homologous Recombination
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2025
Source: Lea-Smith, D. J., et al. Generation of Marked and Markerless Mutants in Model Cyanobacterial Species. J. Vis. Exp. (2016)The video demonstrates a method for generating antibiotic-marked mutants in cyanobacteria. The protocol begins with culturing cyanobacteria, followed by centrifugation and washing steps that preserve surface pili. A plasmid carrying an antibiotic resistance gene flanked by homologous sequences is then introduced. During incubation, the plasmid is internalized via pili...
08:53
Identifying the Effects of BRCA1 Mutations on Homologous Recombination using Cells that Express Endogenous Wild-type BRCA1
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Cited by 15 •
2011
We provide a method for testing BRCA1 variants in a tissue culture based assay for homologous recombination repair of DNA damage by depleting endogenous BRCA1 protein from a cell using RNAi and replacing it with a BRCA1 point mutant that contains a coding change.
FAQs
After a DNA double-strand break, the damaged ends are processed to expose single-stranded DNA. One exposed strand searches for and invades a matching or nearly matching intact duplex, creating a joint molecule. This structure provides a template for accurate DNA synthesis, after which the interacting chromosomes separate and restore continuity.
Sequence similarity allows the exposed single-stranded DNA to pair with an intact duplex that contains the information missing from the damaged chromosome. The invading strand can then guide DNA synthesis using that template. This dependence on related sequence information helps maintain genome integrity while still permitting exchange between homologous chromosomes.
The process preserves genetic information by copying from an intact homologous template rather than relying only on the damaged chromosome. In a meiotic setting, however, exchange between homologous chromosomes can produce new combinations of existing genetic material. Thus, the same underlying mechanism supports accurate repair and contributes to biological variation.
During meiosis, homologous recombination supports accurate pairing and crossing over between homologous chromosomes. Crossing over exchanges corresponding chromosome segments, helping generate genetic diversity among resulting cells. Its template-guided exchange also connects chromosome pairing with the broader need to preserve chromosome information while genetic material is rearranged.
Gene targeting and genome engineering draw on the method’s ability to use a matching sequence as a template for directed DNA change. Researchers can apply these molecular principles to investigate how particular DNA regions behave or to study the consequences of defined genome modifications, extending the process beyond naturally occurring chromosome repair.
Because homologous recombination helps repair damaged chromosomes and preserve genome integrity, changes affecting its molecular principles can provide insight into DNA-repair disorders. Studying the pathway links a cellular repair process with disease-related genome instability and helps researchers examine how defects in chromosome maintenance influence biological outcomes.