Detecting and dating recent shifts in mating systems in flowering plants

• Applicant: Polina Novikova, Ph.D., since 2/2023
• Subject Area: Plant Genetics and Genomics ; Bioinformatics and Theoretical Biology
• Term: from 2021 to 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 462181533

• Final Report Year: 2025

Final Report Abstract

Shifts in mating systems of flowering plants have long-standing consequences on the genetics and evolution of the species. We studied the Arabidopsis lyrata species complex, a close relative of a model system Arabidopsis thaliana. In contrast to self-compatible A. thaliana, A lyrata is mainly self-incompatible. Previously, transitions to self-compatibility have been described in North American A. lyrata and dated at relatively recent evolutionary times, after the last glacial maximum, around 10 Kya. We describe another independent transition to self-compatibility in Siberian A. lyrata and find it more ancient than North American, dating around 90 Kya. Exploring the genetics underlying the transition, we show that it was likely male-driven, starting with the loss of function at the SCR gene, a male component of S-locus. We also show that this transition to self-compatibility had a profound evolutionary impact as it was crucial to establishing a new allotetraploid species, Arabidopsis kamchatica. The establishment of allotetraploid species depends on a quick transition to self-compatibility due to karyotypic differences and incompatibility with diploid progenitors. A. kamchatica inherited the S-allele from the self-compatible Siberian A. lyrata lineage, which lost recognition function but remained dominant over the functional S-allele, inherited from another diploid progenitor, obligate outcrosser, A. halleri. We continue research on A. kamchatica, reconstructing the evolutionary history of the species and its multiple origins and exploring the genetic consequences of the transition to self-compatibility.

Publications

• Transition to Self-compatibility Associated With Dominant S-allele in a Diploid Siberian Progenitor of Allotetraploid Arabidopsis kamchatica Revealed by Arabidopsis lyrata Genomes. Molecular Biology and Evolution, 40(7).
  Kolesnikova, Uliana K.; Scott, Alison Dawn; Van de Velde, Jozefien D.; Burns, Robin; Tikhomirov, Nikita P.; Pfordt, Ursula; Clarke, Andrew C.; Yant, Levi; Seregin, Alexey P.; Vekemans, Xavier; Laurent, Stefan & Novikova, Polina Yu