Disentangling the effects of breakdown of self-incompatibility and transition to selfing in North American Arabidopsis lyrata

Haudry, A., Zha, H., Stift, M. and Mable, B.K. (2012) Disentangling the effects of breakdown of self-incompatibility and transition to selfing in North American Arabidopsis lyrata. Molecular Ecology, 21(5), pp. 1130-1142. (doi:10.1111/j.1365-294X.2011.05435.x)

Full text not currently available from Enlighten.

Abstract

A breakdown of self-incompatibility (SI) followed by a shift to selfing is commonly observed in the evolution of flowering plants. Both are expected to reduce the levels of heterozygosity and genetic diversity. However, breakdown of SI should most strongly affect the region of the SI locus (S-locus) because of the relaxation of balancing selection that operates on a functional S-locus, and a potential selective sweep. In contrast, a transition to selfing should affect the whole genome. We set out to disentangle the effects of breakdown of SI and transition to selfing on the level and distribution of genetic diversity in North American populations of Arabidopsis lyrata. Specifically, we compared sequence diversity of loci linked and unlinked to the S-locus for populations ranging from complete selfing to fully outcrossing. Regardless of linkage to the S-locus, heterozygosity and genetic diversity increased with population outcrossing rate. High heterozygosity of self-compatible individuals in outcrossing populations suggests that SI is not the only factor preventing the evolution of self-fertilization in those populations. There was a strong loss of diversity in selfing populations, which was more pronounced at the S-locus. In addition, selfing populations showed an accumulation of derived mutations at the S-locus. Our results provide evidence that beyond the genome-wide consequences of the population bottleneck associated with the shift to selfing, the S-locus of A. lyrata shows a specific signal either reflecting the relaxation of balancing selection or positive selection.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Haudry, Dr Annabelle and Mable, Professor Barbara and Stift, Mr Marc and Zha, Dr Hong-Guang
Authors: Haudry, A., Zha, H., Stift, M., and Mable, B.K.
College/School:College of Medical Veterinary and Life Sciences > Institute of Biodiversity Animal Health and Comparative Medicine
Journal Name:Molecular Ecology
ISSN:0962-1083
ISSN (Online):1365-294X
Published Online:25 January 2012

University Staff: Request a correction | Enlighten Editors: Update this record

Project CodeAward NoProject NamePrincipal InvestigatorFunder's NameFunder RefLead Dept
551951How colonisation, mating system and selection impact genetic diversity in Arabidopsis lyrataBarbara MableBiotechnology and Biological Sciences Research Council (BBSRC)ISIS 2078Institute of Biodiversity Animal Health and Comparative Medicine
426221Mating systems and genetic diversity in Arabidopsis lyrataBarbara MableNatural Environment Research Council (NERC)NE/D013461/1Institute of Biodiversity Animal Health and Comparative Medicine
442951Leveraging the genome sequences of two arabidopsis relatives for evolutionary and ecological genomicsBarbara MableBiotechnology and Biological Sciences Research Council (BBSRC)BB/E024734/1Institute of Biodiversity Animal Health and Comparative Medicine