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08:01
Identification of Homologous Recombination Events in Mouse Embryonic Stem Cells Using Southern Blotting and Polymerase Chain Reaction
Published on: November 20, 2018
Cis- and trans-acting elements regulate the mouse Psmb9 meiotic recombination hotspot
Frédéric Baudat1, Bernard de Massy
1Institute of Human Genetics, Centre National de la Recherche Scientifique, Unité Propre de Recherche, Montpellier, France.
Plos Genetics
|June 26, 2007
Summary
Genetic factors controlling meiotic recombination hotspots in mice were investigated. A distant element activates recombination near Psmb9, while a nearby element represses it, revealing complex regulation.
Area of Science:
- Genetics
- Molecular Biology
- Reproductive Biology
Background:
- Homologous recombination is crucial during meiosis but unevenly distributed, with hotspots influencing its frequency and location.
- Understanding the genetic regulation of mammalian meiotic recombination hotspots is vital but remains poorly understood.
Purpose of the Study:
- To identify genetic factors controlling the activity of a specific meiotic recombination hotspot near the Psmb9 gene in mice.
- To analyze recombination regulation in both male and female germ lines and across different mouse hybrids.
Main Methods:
- Characterization of a Psmb9 recombination hotspot using sperm typing in various mouse hybrids.
- Analysis of recombination frequency and distribution in male and female germ lines.
- Investigating cis- and trans-acting regulatory elements affecting recombination initiation.
Main Results:
- A trans-acting, haplotype-specific element was found to activate recombination at the Psmb9 hotspot approximately 2,000-fold.
- A cis-acting, haplotype-specific element, likely due to polymorphisms within the initiation zone, represses recombination initiation.
- Subtle variations in recombination frequency and distribution were observed based on mouse strain and sex.
Conclusions:
- Meiotic recombination regulation primarily occurs at the initiation level.
- This study provides the first detailed analysis of meiotic recombination hotspot control in the mouse genome, highlighting interactions between elements inside and outside the hotspot.
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