Molecular Plasticity under Ocean Warming: Proteomics and Fitness Data Provides Clues for a Better Understanding of the Thermal Tolerance in Fish. Frontiers in physiology Ocean warming is known to alter the performance and fitness of marine organisms albeit the proteome underpinnings of species thermal tolerance are still largely unknown. In this 1-month experiment we assessed the vulnerability of the gilt-head sea bream , taken here as a biological model for some key fisheries species, to ocean warming (control 18°C, nursery ground temperature 24°C and heat wave 30°C). Survival was impaired after 28 days, mainly at 30°C although fishes' condition was unaltered. Muscle proteome modulation was assessed at 14 and 21 days, showing that protein expression profiles were similar between fish exposed to 18 and 24°C, differing from fish exposed to 30°C. Fish subjected to 24°C showed an enhanced glycolytic potential and decreased glycogenolysis mainly at 14 days of exposure. Fish subjected to 30°C also showed enhanced glycolytic potential and up-regulated proteins related to gene expression, cellular stress response (CSR), and homeostasis (mostly cytoskeletal dynamics, acid-base balance, chaperoning). However, inflammatory processes were elicited at 21 days along with a down-regulation of the tricarboxylic acid cycle. Thus, juvenile fish seem able to acclimate to 24°C but possibly not to 30°C, which is the predicted temperature for estuaries during heat waves by the year 2100. This may be related with increasing constraints on organism physiology associated with metabolic scope available for performance and fitness at higher temperatures. Consequently, recruitment of commercial sea breams may be in jeopardy, highlighting the need for improved management plans for fish stocks. 10.3389/fphys.2017.00825

Expression profiling and microbial ligand binding analysis of galectin-4 in turbot (Scophthalmus maximus L.). Chen Jinghua,Zhang Lu,Yang Ning,Tian Mengyu,Fu Qiang,Tan Fenghua,Li Chao Fish & shellfish immunology Galectins are a family of galactoside-binding proteins with an affinity for β-galactosides, involved in mediating fundamental processes including development, inflammation, cell migration and apoptosis. Galectin-4 is a member of tendem-repeat galectins, plays vital roles in intestinal epithelial barrier. Here, one galectin-4 gene was captured in turbot (SmLgals4) contains a 1197 bp open reading frame (ORF). In comparison to other species, SmLgals4 showed the highest similarity and identity both to large yellow croaker. The genomic structure analysis showed that SmLgals4 had conserved exons in the CRD domains compared to other vertebrate species. The syntenic analysis revealed that galectin-4 had the same neighboring genes across all the selected species, which suggested the synteny encompassing galectin-4 region during vertebrate evolution. Subsequently, SmLgals4 was widely expressed in all the examined tissues, with the highest expression level in intestine and the lowest expression level in skin. In addition, SmLgals4 was significantly down-regulated in intestine following both Gram-negative bacteria Vibrio anguillarum, and Gram-positive bacteria Streptococcus iniae immersion challenge. Finally, the rSmLgals4 showed strong binding ability to all the examined microbial ligands. Taken together, our results suggested SmLgals4 plays vital roles in fish intestinal immune responses against infection, but the detailed roles of galectin-4 in teleost are still lacking, further studies are needed to be carried out to characterize whether galectin-4 plays similar roles in teleost intestinal immunity. 10.1016/j.fsi.2018.10.050