Lessons from the Nakaseomyces: mating-type switching, DSB repair and evolution of Ho
Laetitia Maroc1, Cécile Fairhead2
1GQE-Le Moulon, Université Paris-Saclay, INRAE, CNRS, AgroParisTech, Ferme du Moulon, 91190, Gif-sur-Yvette, France.
Current Genetics
|April 8, 2021
Summary
Recent studies in Nakaseomyces yeasts, particularly Candida glabrata, reveal insights into mating-type switching evolution and chromosomal double-strand break repair. These findings highlight differences in DNA repair pathways and potential new roles for the Ho endonuclease.
Area of Science:
- Molecular Biology
- Yeast Genetics
- Evolutionary Biology
Background:
- Mating-type switching in Saccharomyces cerevisiae involves programmed chromosomal breaks initiated by the Ho endonuclease.
- Understanding this system in other yeasts provides evolutionary insights into sexual reproduction and DNA repair mechanisms.
Purpose of the Study:
- To review recent findings on mating-type switching and chromosomal double-strand break (DSB) repair in Nakaseomyces yeasts, focusing on Candida glabrata.
- To explore the evolutionary aspects of the mating-type switching system and its components.
Main Methods:
- Comparative genomic analysis of Nakaseomyces yeasts.
- Laboratory manipulation and genome editing of yeast strains.
- CRISPR-Cas9 induced DNA break repair studies in Candida glabrata.
Main Results:
- Identified possible additional roles for the Ho endonuclease in C. glabrata and Nakaseomyces delphensis.
- Discovered significant differences in DSB repair at central and subtelomeric sexual loci between species.
- Demonstrated that Non-Homologous End Joining (NHEJ) is a highly efficient and accurate repair pathway for CRISPR-Cas9 induced breaks in C. glabrata.
Conclusions:
- The study of mating-type switching in Nakaseomyces yeasts enriches the evolutionary perspective on this phenomenon.
- Significant variations in DSB repair mechanisms exist within the Nakaseomyces clade.
- NHEJ plays a crucial role in maintaining genome integrity in Candida glabrata.
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