Robin Michard

Robin Michard

2019 May - Identification of determining factors for meiotic recombination targeting in bread wheat (Triticum aestivum L.)

Understanding the mechanisms governing meiotic recombination in bread wheat (Triticum aestivum L.) is essential since it is the main tool used by breeders for genetic admixing and obtaining new elite varieties with introgression of regions of interest from exotic genetic resources. To this end, the use in bread wheat of a new biotechnology targeting meiotic recombination developed in yeast by Meiogenix seems to be promising.

This biotechnology, named SpiX, involves a DNA-binding domain fused to the SPO11 protein responsible for DNA double-strand breaks, initiating meiotic recombination or crossovers (CO). The development of a new conservation protocol for wheat immature embryos has improved the conditions for bread wheat transformation through biolistic, and thus for the application of SpiX technology. The exploitation of the wheat genome sequence made it possible to isolate the bread wheat genes for SPO11 proteins.

A novel heterologous complementation of Arabidopsis thaliana mutants for SPO11s with the bread wheat orthologous freshly discovered shows their great conservation of sequence and function within plants and their potential functionality for SpiX biotechnology. Finally, the testing of different DNA-binding domains and different targets along bread wheat 3B chromosome shows that SpiX biotechnology requires adjustments depending on the species in which it has to function.

These results are the opportunity to uncover the targeting of meiotic recombination in a widely cultivated crop species and to understand the mechanisms determining sites for double-strand breaks prior to meiotic recombination in wheat.

Keywords : targeting, recombination, meiosis, Triticum aestivum, SPO11, transgenesis, biotechnology.

Modification date : 27 June 2023 | Publication date : 17 May 2019 | Redactor : Karine Ribeyre