BIBLIOS

Tipo
Artigos em Revista

Tipo de Documento
Artigo Completo

Título
Genomic changes and stabilization following homoploid hybrid speciation of the Oxford ragwort Senecio squalidus

Participantes na publicação
Bruno Nevado (Author)
Dep. Biologia Animal
Dep. Biologia Vegetal
CE3C
Mark A. Chapman (Author)
Adrian C. Brennan (Author)
James W. Clark (Author)
Edgar L.Y. Wong (Author)
Tom Batstone (Author)
Shane A. McCarthy (Author)
Alan Tracey (Author)
James Torrance (Author)
Ying Sims (Author)
Richard J. Abbott (Author)
Dmitry Filatov (Author)
Simon J. Hiscock (Author)

Resumo
Oxford ragwort (Senecio squalidus) is one of only two homoploid hybrid species known to have originated very recently, so it is a unique model for determining genomic changes and stabilization following homoploid hybrid speciation. Here, we provide a chromosome-level genome assembly of S. squalidus with 95% of the assembly contained in the 10 longest scaffolds, corresponding to its haploid chromosome number. We annotated 30,249 protein-coding genes and estimated that ∼62% of the genome consists of repetitive elements. We then characterized genome-wide patterns of linkage disequilibrium, polymorphism, and divergence in S. squalidus and its two parental species, finding that (1) linkage disequilibrium is highly heterogeneous, with a region on chromosome 4 showing increased values across all three species but especially in S. squalidus; (2) regions harboring genetic incompatibilities between the two parental species tend to be large, show reduced recombination, and have lower polymorphism in S. squalidus; (3) the two parental species have an unequal contribution (70:30) to the genome of S. squalidus, with long blocks of parent-specific ancestry supporting a very rapid stabilization of the hybrid lineage after hybrid formation; and (4) genomic regions with major parent ancestry exhibit an overrepresentation of loci with evidence for divergent selection occurring between the two parental species on Mount Etna. Our results show that both genetic incompatibilities and natural selection play a role in determining genome-wide reorganization following hybrid speciation and that patterns associated with homoploid hybrid speciation—typically seen in much older systems—can evolve very quickly following hybridization.


Instituição
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA

Suporte
Current Biology

Identificadores da Publicação
ISSN - 0960-9822

Editora
Elsevier BV



Identificadores do Documento
DOI - https://doi.org/10.1016/j.cub.2024.08.009
URL - https://doi.org/10.1016/j.cub.2024.08.009

Identificadores de Qualidade
SCOPUS Q1 (2023) - 11.8 - Agricultural and Biological Sciences (all)