The evolution of XY recombination: sexually antagonistic selection versus deleterious mutation load.

Détails

ID Serval
serval:BIB_5C77F2084812
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
The evolution of XY recombination: sexually antagonistic selection versus deleterious mutation load.
Périodique
Evolution
Auteur(s)
Grossen C., Neuenschwander S., Perrin N.
ISSN
1558-5646 (Electronic)
ISSN-L
0014-3820
Statut éditorial
Publié
Date de publication
2012
Peer-reviewed
Oui
Volume
66
Numéro
10
Pages
3155-3166
Langue
anglais
Résumé
Recombination arrest between X and Y chromosomes, driven by sexually antagonistic genes, is expected to induce their progressive differentiation. However, in contrast to birds and mammals (which display the predicted pattern), most cold-blooded vertebrates have homomorphic sex chromosomes. Two main hypotheses have been proposed to account for this, namely high turnover rates of sex-determining systems and occasional XY recombination. Using individual-based simulations, we formalize the evolution of XY recombination (here mediated by sex reversal; the "fountain-of-youth" model) under the contrasting forces of sexually antagonistic selection and deleterious mutations. The shift between the domains of elimination and accumulation occurs at much lower selection coefficients for the Y than for the X. In the absence of dosage compensation, mildly deleterious mutations accumulating on the Y depress male fitness, thereby providing incentives for XY recombination. Under our settings, this occurs via "demasculinization" of the Y, allowing recombination in XY (sex-reversed) females. As we also show, this generates a conflict with the X, which coevolves to oppose sex reversal. The resulting rare events of XY sex reversal are enough to purge the Y from its load of deleterious mutations. Our results support the "fountain of youth" as a plausible mechanism to account for the maintenance of sex-chromosome homomorphy.
Mots-clé
Deleterious mutations, fountain of youth, recombination, sex chromosomes, sex determination, sex reversal, sexually antagonistic genes
Pubmed
Web of science
Open Access
Oui
Création de la notice
02/04/2012 16:46
Dernière modification de la notice
20/08/2019 15:14
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