Related Experiment Video
Updated: Jul 19, 2026
14:23
Recombineering Homologous Recombination Constructs in Drosophila
Published on: July 13, 2013
Meiotic recombination: breaking the genome to save it
1Laboratory of Biochemistry, National Cancer Institute, Building 37 Room 6124, Bethesda, Maryland 20892-4255, USA. lichten@helix.nih
Current Biology : CB
|June 20, 2001
Summary
Meiotic recombination, essential for chromosome segregation, is initiated by double-strand DNA breaks. This process is universally conserved and mediated by the enzyme Spo11p.
Area of Science:
- Genetics
- Molecular Biology
- Cell Biology
Background:
- Meiotic recombination is crucial for accurate chromosome segregation during gamete formation.
- The initiation of meiotic recombination is a tightly regulated process.
- Recent research suggests a conserved mechanism for initiating recombination.
Purpose of the Study:
- To elucidate the universal mechanism initiating meiotic recombination.
- To confirm the role of Spo11p in initiating double-strand DNA breaks during meiosis.
Main Methods:
- Analysis of DNA repair pathways.
- Biochemical assays to detect DNA breaks.
- Genetic studies in model organisms.
Main Results:
- Spo11p is confirmed as the enzyme responsible for initiating meiotic recombination.
- The formation of double-strand DNA breaks by Spo11p is a conserved mechanism across species.
- This process is fundamental for successful meiosis.
Conclusions:
- The universal mechanism for initiating meiotic recombination involves Spo11p-mediated double-strand DNA breaks.
- Understanding this process is key to understanding fertility and genetic diversity.
Related Concept Videos
01:34Crossing Over
Unlike mitosis, meiosis aims for genetic diversity in its creation of haploid gametes. Dividing germ cells first begin this process in prophase I, where each chromosome—replicated in S phase—is now composed of two sister chromatids (identical copies) joined centrally.
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process called synapsis.
In order to...
The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process called synapsis.
In order to...
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...
02:08Gene Conversion
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
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...
02:08Gene Conversion
Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the recombination of sequences forms the molecular basis of genomic evolution. Random and non-random permutations of genomic sequences create a library of new amalgamated sequences. These newly formed genomes can determine the fitness and survival of cells. In bacteria, homologous and non-homologous types of recombination lead to the evolution of new...
01:30Crossing Over
Crossing over is the exchange of genetic information between homologous chromosomes during prophase I of meiosis I. Genetic recombination gives rise to allelic diversity in the newly formed daughter cells. In humans, crossing over produces genetically distinct haploid egg and sperm cells that undergo fertilization to produce unique offspring. Before cell division starts, the germ cell’s chromosome(s) undergo duplication in the S phase of the cell cycle. As the cells enter prophase I, duplicated...