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Detection of Homologous Recombination Intermediates via Proximity Ligation and Quantitative PCR in Saccharomyces cerevisiae
Published on: September 11, 2022
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C-DNA may facilitate homologous DNA pairing.
Alexey K Mazur1, Eugene Gladyshev2
1CNRS, Université Paris Cité, UPR 9080, Laboratoire de Biochimie Théorique, 13 rue Pierre et Marie Curie, Paris, France; Institut Pasteur, Université Paris Cité, Group Fungal Epigenomics, Paris, France.
Trends in Genetics : TIG
|February 21, 2023
Summary
Homologous DNA pairing, crucial for chromosome biology, may involve direct DNA molecule interactions. This process might utilize the C-DNA structure, facilitating DNA homology recognition without recombination.
Area of Science:
- Chromosome biology
- Molecular genetics
- Biophysics
Background:
- Recombination-independent homologous pairing is a key but poorly understood aspect of chromosome biology.
- Studies in Neurospora crassa suggest direct pairing of homologous DNA molecules underlies this process.
Purpose of the Study:
- To investigate the DNA structures consistent with genetic findings on homologous pairing.
- To propose a model for recombination-independent homologous DNA recognition.
Main Methods:
- Theoretical modeling of DNA structures.
- All-atom molecular modeling.
Main Results:
- A model was developed where paired homologous DNA double helices adopt a conformation shifted towards C-DNA.
- C-DNA's shallow major groove may facilitate initial homologous DNA contacts.
- This C-DNA conformation is consistent with genetic data from Neurospora crassa.
Conclusions:
- The C-DNA conformation is a plausible structural basis for recombination-independent homologous pairing.
- Discovering C-DNA's biological functions could elucidate DNA homology recognition mechanisms.
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