The body temperature of most fishes equilibrates rapidly with ambient temperature, so water temperature is suggested to be the abiotic master factor which virtually controls and limits all the biochemical, physiological and life history activities. In comparison with adults, fish larvae are more susceptible to temperature variation. Investigating mechanisms underlying the acclimation process of fish larvae to temperature stress is of big significance to aquaculture and ecological research. 

The research group led by Prof. Zongbin Cui at Institute of Hydrobiology, Chinese Academy of Sciences (IHB) studied the transcriptional response of larval zebrafish to cold or heat stress. Larvae at 96 hpf (hours post fertilization) were exposed to 16℃ (low temperature), 28℃ (control) and 34℃ (high temperature) for 2h and 48h, and the expression of genes was characterized using microarray. A total of 2680 genes were found to be differentially expressed after exposed to cold orheat stress and most of which have not been reported to be associated with temperature stress previously. Bioinformatic analyses reveal that genes up-regulated by temperature stress are mainly involved in biological process including regulation of transcription, nucleosome assembly, chromatin organization, protein folding, RNA processing, cellular metal ion homeostasis and protein transport. 

This study has identified a large number of genes specifically regulated by cold or heat stress and revealed the critical biological processes and pathways potentially regulated by temperature stress. These findings provide new clues for investigation of gene expression regulatory networks upon temperature stress in fish. 

This work was supported by grants from the National Natural Science Foundation and the National High-tech R&D (863) Program of China. The results have been published inPLoS ONE (http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0037209).