Effect of seasonal high temperature on the immune response in Apostichopus japonicus by transcriptome analysis

The sea cucumber Apostichopus japonicus is a flourishing aquaculture species in China. However, there are challenges for sea cucumber aquaculture, one of which is the high temperature in summer. In this study, we explored the transcriptome expression profiles with seasons (APR, JUN and JUL) in the muscle tissue of A. japonicus. The temperature of the natural coast was 13 °C, 21 °C and 25 °C respectively when sampling. Compared with APR group, changes of expression profiles were more significant in JUL group than that in JUN group. A total of 46 differential expressed genes (DEGs) involved in both innate and adaptive immunity were highlighted, including 27 up-regulated and 19 down-regulated genes. They were further grouped into 10 sub-classes: heat shock, coagulation cascades, antigen processing and presentation, inflammatory response, transporter activity, immunoglobulin, lectin C, cell adhesion, reactive oxygen species (ROS) scavenging, apoptosis and autophagy. The study will offer deep insights of the molecular mechanisms underlying the physiological responses to seasonal high temperature in A. japonicus. Particularly, knowledge about the immunological effects of seasonal temperature on the species is critical for the optimal management practices for both wild and aquaculture populations.