MACS · Mechanisms for crossover regulation in Allopolyploid Camelina sativa

To meet the demands of climate resilient and sustainable agriculture, advanced breeding strategies must harness novel genetic variation. Introgression - the transfer of beneficial alleles from wild or related species into crops - is a key approach to achieve these objectives. However, this approach is still limited by our current understanding of the requirements for crossover (CO) formation - an essential mechanism that enables gene exchanges during meiosis between divergent chromosomes. Natural allopolyploids are ideal for studying CO formation between divergent chromosomes because they result from interspecific hybridization followed by genome duplication, producing homoeologous chromosomes - similar but slightly divergent arising from different parental species. MACS project will investigate the potential common mechanisms that could regulate the efficiency of COs between homoeologs. Specifically, it will address: (1) whether the main CO pathway (Class I) mediates COs between homoeologs and if its efficiency can be modulated; and (2) whether early meiotic chromosome movements suppress homoeolog interactions thereby limiting COs between homoeologs. To study these objectives Camelina sativa is selected as the model due to its relevance as a resilient oilseed crop relevant to EU agriculture and its unique genomic structure: it possesses three subgenomes (A, B, C) yet displays diploid-like meiosis, indicating suppression of COs between homoeologs. Hence MACS will also characterize the meiotic “toolbox” of C. sativa, focusing on its meiotic adaptation to polyploidy. This interdisciplinary project integrates genomics, bioinformatics, and cytology. The expected outcomes include both fundamental insights and practical innovations to enhance introgression efficiency and targeted plant breeding strategies. MACS aligns with the MSCA's goals and will enhance the applicant’s professional experience, competencies and contribute to sustainable agriculture.