Alternative splicing plays a nonredundant role in greater amberjack (Seriola dumerili) in acclimation to ambient salinity fluctuations

Abstract

Alternative splicing (AS) is an important post-transcriptional mechanism for adaptation of fish to environmental stress. Here, we performed a genome-wide investigation to AS dynamics in greater amberjack (Seriola dumerili), an economical marine teleost, in response to hypo- (10 ppt) and hyper-salinity (40 ppt) stresses. Totally, 2267–2611 differentially spliced events were identified in gills and kidney upon the exposure to undesired salinity regimes. In gills, genes involved in energy metabolism, stimulus response and epithelial cell differentiation were differentially spliced in response to salinity variation, while sodium ion transport and cellular amide metabolism were enhanced in kidney to combat the adverse impacts of salinity changes. Most of these differentially spliced genes were not differentially expressed, and AS was found to regulate different biological processes from differential gene expression, indicative of the functionally nonredundant role of AS in modulating salinity acclimation in greater amberjack. Together, our study highlights the important contribution of post-transcriptional mechanisms to the adaptation of fish to ambient salinity fluctuations and provides theoretical guidance for the conservation of marine fishery resources against increasingly environmental challenges.