A vertebrate reproductive system involving three ploidy levels : hybrid origin of triploids in a contact zone of diploid and tetraploid green toads (Bufo viridis subgroup)

Détails

ID Serval
serval:BIB_0EC986ED79F4
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
A vertebrate reproductive system involving three ploidy levels : hybrid origin of triploids in a contact zone of diploid and tetraploid green toads (Bufo viridis subgroup)
Périodique
Evolution
Auteur(s)
Stöck M., Ustinova J., Lamatsch D K., Schartl M., Perrin N., Moritz C.
ISSN
0014-3820
Statut éditorial
Publié
Date de publication
2010
Peer-reviewed
Oui
Volume
64
Numéro
4
Pages
944-959
Langue
anglais
Résumé
The rise and consequences of polyploidy in vertebrates, whose origin was associated with genome duplications, may be best studied in natural diploid and polyploid populations. In a diploid/tetraploid (2n/4n) geographic contact zone of Palearctic green toads in northern Kyrgyzstan, we examine 4ns and triploids (3n) of unknown genetic composition and origins. Using mitochondrial and nuclear sequence, and nuclear microsatellite markers in 84 individuals, we show that 4n (Bufo pewzowi) are allopolyploids, with a geographically proximate 2n species (B. turanensis) being their maternal ancestor and their paternal ancestor as yet unidentified. Local 3n forms arise through hybridization. Adult 3n mature males (B. turanensis mtDNA) have 2n mothers and 4n fathers, but seem distinguishable by nuclear profiles from partly aneuploid 3n tadpoles (with B. pewzowi mtDNA). These observations suggest multiple pathways to the formation of triploids in the contact zone, involving both reciprocal origins. To explain the phenomena in the system, we favor a hypothesis where 3n males (with B. turanensis mtDNA) backcross with 4n and 2n females. Together with previous studies of a separately evolved, sexually reproducing 3n lineage, these observations reveal complex reproductive interactions among toads of different ploidy levels and multiple pathways to the evolution of polyploid lineages.
Mots-clé
Genomic plasticity, polyploidy, population genetics, vertebrates
Web of science
Création de la notice
30/04/2010 18:31
Dernière modification de la notice
20/08/2019 13:35
Données d'usage