ExpoSEED is composed of six work packages, WP2, WP3, WP4 and WP5 are focused on scientific aspects, WP1 is entirely dedicated to the coordination and management of the Action while WP6 develops training and dissemination activities. The scientific activities all converge on WP4, as represented in the attached images.
WP2 exploited a reverse genetics approach (from the candidate gene to phenotype) to identify key factors that control yield, in terms of seed number and size, in model species as Arabidopsis and rice. The information gained on model species have been tested and transferred to cereals as wheat and barley and to other distantly related species belonging to the poppy, tomato and coffee families. During the project the partners identified key factors acting as master regulators in controlling branching, carpel and seed differentiation. The functional characterization (WP4) of a subset of selected factors led to a more detailed description of the molecular pathways that control specific developmental stages with determinant effects on yield. Interestingly, strong interconnections with auxin and cytokinin metabolism have been described. Part of the information gained on model species, together with the identification of novel pathways controlling kernel formation, have been transferred to crop species in order to identify key genes that can be manipulated to increase yield in the very next future.
WP3 is strongly interconnected with WP2 and it is based on the observation that genetic variability can be exploited to search for novel functional alleles in the selected candidate genes. This approach has been mainly exploited in cereals, wheat and barley leading to the identification of promising novel alleles.
WP5 uses a complementary approach, named forward genetics (from the phenotype to the causal genes), that is expected to lead to the identification of novel factors that will be characterized within WP4. This strategy is only performed on crops as wheat and barley and it is based on the observation of specific phenotypes. Once a phenotype, for instance high yield, is detected in germplasm collections or in populations, statistical analysis is performed to identify the genetic locus correlated with the selected phenotype. Barley, durum wheat and bread wheat collections have been analyzed in different growing conditions to identify genotypes specifically adapted to the selected environment. QTL analysis or GWAS approaches have been performed to identify the combination of genetic loci conferring the better plant performance (novel loci influencing yield and gluten content have been identified).
Finally, WP4 collected the information from the other WPs, promising candidate genes (WP2), alleles (WP3) and genetic loci (WP5) to further proceed with the functional characterization. To do this, the partners used a wide variety of techniques (detailed expression profile studies, protein-protein and protein-DNA interaction experiments, development of mutant lines, microscopy analysis) to finally describe the precise function of selected genes.
Altogether, the ExpoSEED’s WPs and the collaboration between the partners expanded the knowledge on the mechanisms that control different aspects, all related to yield determination in model and crop species. Specific value has been added to the Action through the secondments between staff members, this indeed expanded the knowledge and techniques exploited in each laboratory to reach specific aims.
