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Updated: Dec 27, 2025
09:24
Preparation of Meiotic Chromosome Spreads from Mouse Oocytes for Assessment of Synapsis and Recombination
Published on: July 18, 2025
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Pioneering meiotic recombination.
Kris G Alavattam1,2,3, Hironori Abe1,2,3, Satoshi H Namekawa1,2,3
1Division of Reproductive Sciences, University of Cincinnati College of Medicine, Cincinnati, Ohio, 45229, USA.
Genes & Development
|March 4, 2020
Summary
Pioneer factors, including PRDM9 and HELLS, form a complex that opens chromatin to initiate meiotic recombination. This finding expands the role of pioneer factors beyond gene regulation to other crucial biological events.
Area of Science:
- Epigenetics and Chromatin Biology
- Meiosis and Genetic Recombination
- Molecular Mechanisms of DNA Regulation
Background:
- Pioneer factors are known to open inaccessible chromatin for gene regulation.
- Their roles in physiological events beyond transcription remain largely unexplored.
- Meiotic recombination initiates with DNA double-strand breaks at specific genomic locations.
Purpose of the Study:
- To investigate the function of pioneer factors in meiotic recombination.
- To identify the molecular players involved in chromatin remodeling during meiosis.
- To determine if pioneer factors operate in processes other than transcriptional regulation.
Main Methods:
- Identification and characterization of a novel pioneer complex.
- Analysis of the roles of PRDM9 (a zinc finger DNA-binding protein) and HELLS (an SNF2 family chromatin remodeler).
- Experimental determination of recombination hot spot designation.
Main Results:
- A pioneer complex, comprising PRDM9 and HELLS, was identified in mouse meiotic recombination.
- This complex exposes nucleosomal DNA to designate sites for DNA double-strand breaks.
- Both HELLS and PRDM9 are essential for determining meiotic recombination hot spots.
Conclusions:
- The study identifies a pioneer complex critical for initiating meiotic recombination.
- This discovery broadens the known functions of pioneer factors to include chromatin remodeling for meiotic events.
- Pioneer factors play a significant role in biological processes beyond transcriptional regulation.
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