Transcriptional response of golden pompano Trachinotus ovatus larvae to cold and heat stress

In order to investigate the molecular response pattern of golden pompano Trachinotus ovatus larvae under cold and heat stress, transcriptome sequencing was performed in three temperature-treated groups (24 °C, low temperature, LT; 28 °C, moderate temperature, MT; and 32 °C, high temperature, HT) after one week of treatment. A total of 501,367,768 clean reads were obtained, with an average GC content of about 47 %. 94,144 unigenes were recovered, with an average length of 1045 bp. Gene ontology (GO) analysis and Kyoto encyclopedia of genes and genomes (KEGG) analysis showed that a large number of differentially expressed genes were related to metabolic processes, protein synthesis and nutrient digestion and absorption. The differentially expressed genes (DEGs) were most highly enriched into the pathways including protein digestion and absorption, fat digestion and absorption, starch and sucrose metabolism, vitamin digestion and absorption, glutathione metabolism. High temperature may inhibit the secretion of type II collagen by down-regulating the expression of Shh and Sox9a genes. The results of this study provide important support for understanding mechanism of the response to high temperature in Trachinotus ovatus and guiding relevant production practices.