RecHybrid: Regulation of meiotic recombination in Arabidopsis and tomato hybrids by MutS-dependent sensitivity to genetic polymorphism

• Applicant: Charles Underwood, Ph.D.
• Subject Area: Plant Genetics and Genomics
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 465339501

Meiosis is a unique cell division that occurs in all sexually reproducing organisms to generate recombined, haploid gametes. During meiosis homologous chromosomes pair and reciprocal exchanges, so-called crossovers, of genetic material occur. The location of crossovers on chromosomes is non-random and is shaped by various factors including genetic polymorphism, chromatin and centromere positioning. In this project we will explore the role of a variety of mismatch repair (MutS) protein complexes in the regulation of meiotic recombination in genetically polymorphic plant hybrids. We propose three highly integrated work packages to comprehensively understand the role of these complexes during meiosis in the model plant Arabidopsis thaliana (AMU-Poznan), and the crop species, tomato (MPIPZ-Cologne). Firstly, we will determine the roles of the different MutS complexes by generating genome-wide crossover maps in mutant hybrids from both model systems. In Arabidopsis, we will test a more exhaustive list of mutant combinations, while in tomato we will work on a focused set of mutants in a series of hybrids between the cultivated tomato and related wild species. Secondly, we will understand how the direct juxtaposition of homozygous and heterozygous chromosomal regions can alter meiotic crossover distribution in Arabidopsis and tomato. In Arabidopsis, we will characterize the genetic pathways involved in this effect, while in tomato we aim to establish whether the effect is conserved in a different, and economically valuable, plant species. Finally, we will develop fine-scale insights into the mechanistic basis of crossover/non-crossover choice in polymorphic Arabidopsis genotypes by making use of a novel seed-typing method that we have recently developed. Researching a common theme, sensing of polymorphism by MutS complexes during meiosis, in two plant models with different genome structures and polymorphism patterns will allow us to develop deep insights into the role of these complexes in meiosis. In the proposed project we propose to have two scientific exchanges where the Cologne group will visit to Poznan, and vice versa. The expected outputs of the project would not be reached if the projects were implemented independently. Overall, we look forward to building on our strong track record of previous collaborations by beginning this new joint project and igniting a strong, powerful Polish-German collaboration.

• DFG Programme: Research Grants
• International Connection: Poland
• Partner Organisation: Narodowe Centrum Nauki (NCN)
• Cooperation Partner: Professor Dr. Piotr Ziolkowski