Abstracts (first author)
Differential gene expression in a non-model fish species with alternative mating tactics
Social dominance is important for the reproductive success of males in many species. In fish with external fertilization, it is not as apparent which traits are necessary to become dominant or territorial and what benefits the socially dominant individual. In the black-faced blenny (Tripterygion delaisi) during the reproductive season, some males change color and invest in nest making and defense, whereas sneaker males do not change color and ‘sneak’ reproductions when females lay their eggs. Using RNAseq, we profiled differential gene expression between the brains of territorial males, sneaker males, and females to study the molecular signatures of male dimorphism. Despite several studies reporting high levels of genetic differentiation between sexes, we found that more genes were differentially expressed between the two male phenotypes than between males and females. This suggests that phenotypic plasticity is a more important factor in differential gene expression than sexual dimorphism during the reproductive period. For the dominant male, expression was higher in genes mainly related to cytoskeletal rearrangement indicating the drastic change in behavior and phenotype. We also identified novel genes which are differentially expressed in the brain tissue between the two male mating types in Tripterygion delaisi, which can be further investigated in other fish species with similar mating tactics.