Genomic analyses of the Linum distyly supergene reveal convergent evolution at the molecular level

• DOI: 10.1016/j.cub.2022.08.042
• Publication Date: 2022-09-09T15:07:22Z
• Authors: Juanita Gutiérrez...; Marco Fracassetti; Emma L. Berdan; Ignas Bunikis; Lucile Soler; Jacques Dainat; Verena E. Kutschera; Aleksandra Losvik; Aurélie Désamoré; P. William Hughes; Alireza Foroozani; Benjamin Laenen; Edouard Pesquet; Mohamed Abdelaziz; Olga Vinnere Pett...; Björn Nystedt; Adrian C. Brennan; Juan Arroyo; Tanja Slotte
• Keywords: Supergene (geology)

Supergenes govern multi-trait-balanced polymorphisms in a wide range of systems; however, our understanding their origins and evolution remains incomplete. The reciprocal placement stigmas anthers pin thrum floral morphs distylous species constitutes an iconic example balanced polymorphism governed by supergene, the distyly S-locus. Recent studies have shown that Primula Turnera supergenes are both hemizygous thrums, but it unknown whether hemizygosity is pervasive among S-loci. As has major consequences for supergene loss, clarifying this genetic architecture shared critical. Here, we characterized Linum generating chromosome-level genome assembly tenue, followed identification S-locus using population genomic data. We show thrum-specific expression S-linked genes, including pistil-expressed candidate gene style length, features Structural variation likely instrumental recombination suppression, although non-recombining dominant haplotype accumulated transposable elements, genes not under relaxed purifying selection. Our findings reveal remarkable convergence independently derived supergenes, provide counterexample to classic inversion-based shed new light on origin maintenance polymorphism.