Developmental gene expression time series have been collected in both Atlantic salmon and Rainbow trout including a number of tissues (including heart, tail, gills, jaw, brain (hypothalamus), pituitary gland, eye, skin, muscle, liver, gonads (ovary, testis), adipose tissue) in series of families that exhibit polymorphisms for seven life-history genes. Further, we have succeeded in optimizing a highly economical gene expression analysis approach which enabling a much more in depth analysis than previously planned. This material is currently being analysed . We have progressed furthest looking at gene networks associated with the vgll3 gene e.g.
Verta, et al (2024). A complex mechanism translating variation of a simple genetic architecture into alternative life histories. PNAS 121(48), e2402386121.
The same salmon and trout have also been measured for a number of phenotypic traits and subsets of individuals have been measured for activity level, fatness and bone density. Each individual is individually tagged, so we can calculate individual growth over 1-2 year periods. We have also included a long term food restriction trial for assessment of gene x environment interactions.
A Europe-wide collaboration is progressing well, and included a common workshop in March 2024, and the partners have been active in providing samples and data for our analyses. We have also successfully optimised the SNP panel in this material and genetic analyses are well underway. We have also submitted the first manuscript for publication from this material.
We have also commenced collection of environmental data for WP2.3 but most analyses will take place in years 3 and 4 of the project. One early example of the results expected from this work has been published for the vgll3 gene in Miettinen, et al. (2024). Temporal allele frequency changes in large-effect loci reveal potential fishing impacts on salmon life-history diversity. Evolutionary Applications, 17(4), e13690.
Considering research in wild populations, we have identified sex-specific overdominance for reproductive success based on the vgll3 locus genotypes (Mobley, et al (2024). Sex-specific overdominance at the maturation vgll3 gene for reproductive fitness in wild Atlantic salmon. Molecular Ecology, 33(14), e17435. As a part of the developmental time series sampling, and phenotypic measurements outlined earlier, we will include a sex comparison in future research.
Modelling life history trait research has expanded the parameters of a previously published individual-based model (manuscript submitted for publication).
