Periodic Reporting for period 1 - FishLEGs (Life-history genes in fishes: bridging functional and evolutionary genetics for understanding life-history trait evolution)
Berichtszeitraum: 2023-01-01 bis 2025-06-30
Life history is one of the most central concepts in biology and tremendous effort has been put into investigating the causes and consequences of variation in reproduction and survival, i.e. evolutionary fitness. But even in well studied model organisms such as mice and humans the path from genes to the morphological and physiological characteristics of individuals often remains a black box. A strategy to overcome this hurdle has recently emerged, with the discovery of genes tightly linked with variation in various life history traits. These “life-history genes” offer new opportunities to study not just the why (evolution), but also the how (functional genetics) of life history trait variation. The project is addressing critical outstanding questions by bridging molecular and evolutionary genetics approaches to study life history genes linked with life-history traits including age at maturity, migration timing and migration strategy in 3 fish species: Atlantic salmon, Rainbow trout/steelhead and Atlantic cod. This research also has societal relevance for health, sustainable fisheries, conservation and climate resilience.
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).
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).
The findings of the Verta et al. study are beyond state of the art as The sheer number of genes that vgll3 influences the expression of was unexpected.The findings of Mobley et al. are also state of the art as the study revealed sex-specific selection on a gene responsible for an important lifehistory trait.