Ocean-Warming During Embryogenesis Programs a Lasting Transcriptomic Signature in Fishes
Exposure to elevated temperatures during embryogenesis can influence the plasticity of tissues in later-life. Despite these long-term changes in plasticity, few differentially expressed genes are ever identified, suggesting that the developmental programming of later-life plasticity may occur through the modulation of other aspects of the transcriptomic architecture, such as gene network function. Here, we use network modelling approaches to demonstrate that warm temperatures during embryonic development (developmental warming) have consistent effects in later-life on the organisation of transcriptomic networks across four diverse species of fishes: Scyliorhinus canicula, Danio rerio, Dicentrarchus labrax, and Gasterosteus aculeatus. The transcriptomes of developmentally warmed fishes are characterised by an increased entropy of their pairwise gene interaction networks, implying a less structured, more random set of gene interactions. We also show that, in zebrafish subject to developmental warming, the entropy of an individual gene within a network is associated with that genes probability of expression change during temperature acclimation in later-life. However, this association is absent in animals reared under control conditions. Thus, the thermal environment experienced during embryogenesis can alter transcriptomic organisation in later-life, and these changes may influence an individuals responsiveness to future temperature challenges.