conference schedule and program with abstracts - Horticulture ...

P-7
Impact of human selection on the allelic diversity of genes involved into the anthocyanin
pathway
A. Fournier-Level 1 , L. Le Cunff 2 , T. Lacombe 1 , J-P. Péros 1 , A. Dereeper 1 , B. Bacilieri 1 , J.M.
Boursiquot 1 , P. This* 1
1 UMR DIAPC INRA-Montpellier Supagro, Montpellier, France; 2 UMT Geno Vigne, IFV-
INRA-Montpellier Supagro, Montpellier, France
*Corresponding author: this@supagro.inra.fr
Berry skin colour, and indirectly the anthocyanin content, is probably one of the agronomical
traits most easily selected by human during the history of the grapevine. Consequently the
anthocyanin biosynthesis pathway has very interesting features for the study of gene network
evolution. Moreover, the structural genes involved in this pathway are identified and
characterized and regulatory genes (VvMybAs) of this pathway are also known. Our recent data
suggest that the genetic determinism of the total variation of anthocyanin content, and by
extension the berry skin colour, in cultivated grapevine is rather due to few mutations within the
sequences of the regulatory VvMybAs genes than mutations in anthocyanin structural genes. We
have sequenced the VvMybAs genes on a core-collection of cultivated grapevine in order to
understand the evolution of the genes at the allelic level and to identify the order of emergence of
the principal mutations linked with the anthocyanin content. Secondly, we have sequenced the
anthocyanin structural genes on another sample consisting of Vitis Vinifera L. (cultivated and
wild) and other species of Vitis to identify the direct and indirect impact of human selection in
these genes. These studies showed that berry color-associated mutations evolved from wild black
alleles to a pink allele (SNP variation in coding sequence of VvMybA2) and to the white one
(Insertion of Gret1 in the promoter of VvMybA1). We have also identified a significant link
between the positions of genes in the anthocyanin pathway and their level of divergence. More
surprisingly, comparison between values of Tajima’s D and Fay and Wu’s H of the wild and
cultivated samples for each gene showed a different impact of the selection pattern and different
selected targets within these two samples. This analysis is an interesting example for developing
this kind of study at a whole genome level.
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