Transcriptome profiling and histology change of juvenile blunt snout bream (Megalobrama amblycephala) liver tissue in response to acute thermal stress. Megalobrama amblycephala

The set of genes identified showed regulatory modulation at different temperature, and these genes are possible specific candidates that may be investigated, in addition to liver histology examinations, for further studies aimed at determining how M. amblycephala livers exhibit damage under high temperature stress and the possible roles of reactive oxygen species in this process. Overall design: Previous studies have investigated the physiological responses to acute thermal stress in fish; however, little information is available for the underlying molecular mechanisms to changing temperatures in aquatic ecosystems. In an effort to understand the underlying mechanisms and the pathways activated by high temperature, we sampled livers from juvenile Megalobrama amblycephala exposed to control (25 °C) and test (35 °C) condition and performed short read (100 bp) next generation RNA sequencing (RNA-seq). The RNA-seq reads from all the exposures were assembled into unigenes datasets according to an available reference transcriptome. Using reads from each nitrite concentration, we performed RNA-seq based gene expression analysis that identified total 440 differentially expressed genes. The differentially expressed genes were related to oxidative stress, apoptosis, immune responses and the metabolism of proteins and fats. The differential mRNA expression of selected genes involved in antioxidant enzymes, apoptosis gene and heat shock proteins in response to stress was verified by quantitative real-time reverse transcriptase polymerase chain reaction.