Principle : Paleogenomics can be used as a guide for traits dissection.
This task aims at demonstrating that rapid and massive structural (i.e. duplication-derived gene loss) and functional (i.e. duplication-mediated neo- or sub-functionalisation) changes following WGD might provide the ability of polyploids to quickly adapt or survive to environmental conditions, not tolerated in their diploid ancestors though the elaboration of new phenotype/traits in order to for example (i) increased vigour, or (ii) favoured tolerance to a wider range of biotic and abiotic environmental stresses, or (iii) facilitated self-fertilization , or(iv) the formation of asexually reproducing (apomictic) species. When can then speculate that de novo biological pathways, inherited from duplicated gene copies, may have delivered improved and more adapted traits to face new environmental constraints. We proposed to investigate the role of polyploidization onto the elaboration of complex trait components focussing our approach on traits that are actually investigated in breeding programs: yield components, end-use values and technological use values. In order to test this hypothesis, it is necessary to clone the genes underlying the QTL that could be included in this scheme, i.e. in a paralogous position and/or are conserved between species. Using the paleogenomics data as a guide to dissect traits in bread wheat, information gained from genes in models (such as rice), can be transferred in bread wheat for which a functional ortholog has been identified, i.e. the translational research approach. Following this strategy, we have identified genes in bread wheat driving key traits such as Nitrogen use efficiency (GoGAT, Quraishi & Abrouk et al. 2011, EuropeanPatent10290058), flowering (VRN), tillering (TIN), grain fiber content (GFC, Quraishi & Murat et al. 2011), grain carotenoid content (PSY, Dibari et al. 2012) and spike architecture (FZP, Dobrovolskaya et al. 2015).
Translational research (Salse 2015) – The figure illustrates the paleogenomics data (left) used to dissect traits (right). The PlantSyntenyViewer tool deliver a list of robust orthologous genes for any region of interest (left). Mutants from Brachypodium and wheat for a conserved ancestral gene show the identification of a conserved functional ortholog involved in the spike architecture in both species.