Hur förutsägbar är den genetiska basen för evolutionär förändring på art- och populationsnivå? Om effekten av genomduplicering och historia
Tidsperiod: 2013-01-01 till 2015-12-31
Projektledare: Martin Lascoux
Budget: 2 241 000 SEK
Polyploidy, or whole genome duplication (WGD) occurs in virtually all vascular plants and has played a major role in evolution. Here we leverage the recent developments in sequencing technology and previous studies in the Capsella genus to characterize genomic and phenotypic changes associated to WGD in C. bursa-pastoris, a recently formed tetraploid weed. We will first conduct whole-genome resequencing and gene expression studies of 24 accessions, 12 from Europe and 12 from China. In a second step, the association between genomic variation and adaptive traits will be assessed through association and linkage mapping. These data, together with data from its two diploid relatives, will be used to assess changes associated to WGD and address two sets of questions. The first set is concerned with the genomic consequences of WGD between species and between populations within species: Which genomic regions have been deleted after WGD and are some functional groups more affected than others? Has WGD led to genome-wide relaxation of natural selection in polyploids? Do gene duplicates resulting from WGD evolve more slowly than singletons? Are evolutionary rates correlated to differences in expression levels and patterns? The second set of questions will bear on the consequences of WGD for putative adaptive traits: How much of the genetic architecture of a trait is conserved after WGD? Does WGD lead to a significant change in the suite of genes controlling major adaptive traits?