The Silene latifolia genome and its giant Y chromosome

Journal: Science

Authors: Moraga C, Branco C, Rougemont Q, Jedlička P, Mendoza-Galindo E, Veltsos P, Hanique M, Rodríguez de la Vega RC, Tannier E, Liu X, Lemaitre C, Fields PD, Cruaud C, Labadie K, Belser C, Briolay J, Santoni S, Cegan R, Linheiro R, Adam G, El Filali A, Mossion V, Boualem A, Tavares R, Chebbi A, Cordaux R, Fruchard C, Prentout D, Velt A, Spataro B, Delmotte S, Weingartner L, Toegelová H, Tulpová Z, Cápal P, Šimková H, Štorchová H, Krüger M, Abeyawardana OAJ, Taylor DR, Olson MS, Sloan DB, Karrenberg S, Delph LF, Charlesworth D, Muyle A, Giraud T, Bendahmane A, Di Genova A, Madoui MA, Hobza R, Marais GAB.

Year: 2025

ISBN: doi: 10.1126/science.adj7430

Abstract

In many species with sex chromosomes, the Y is a tiny chromosome. However, the dioecious plant Silene latifolia has a giant ~550-megabase Y chromosome, which has remained unsequenced so far. We used a long- and short-read hybrid approach to obtain a high-quality male genome. Comparative analysis of the sex chromosomes with their homologs in outgroups showed that the Y is highly rearranged and degenerated. Recombination suppression between X and Y extended in several steps and triggered a massive accumulation of repeats on the Y as well as in the nonrecombining pericentromeric region of the X, leading to giant sex chromosomes. Using sex phenotype mutants, we identified candidate sex-determining genes on the Y in locations consistent with their favoring recombination suppression events 11 and 5 million years ago.

https://pubmed.ncbi.nlm.nih.gov/39913565/