Transcriptome analysis reveals reduced immunity and metabolic level under cold stress in Mauremys mutica

Abstract

The yellow pond turtle (Mauremys mutica) is widely cultured for food, medicine and for keeping as pets in China. The high risk of disease outbreaks and mortality caused by sudden sharp temperature drop events has significant negative effects on the aquaculture industry of M. mutica. However, the mechanism underlying the damage caused by cold stress is still unclear. To fill this gap, we performed transcriptome sequencing of M. mutica samples collected at three sampling time points (3h, 24h and 48h) during cold treatment, and at a recovery time point (96 h after the end of cold stress). The results showed that immunity and metabolism-related pathways (neuroactive ligand-receptor interactions, cytokine-cytokine receptor interactions and NOD-like receptor signaling pathways) were significantly enriched at both 24h and 48h. The expression of immunity and metabolism-related genes (BS2A1, PIWIL2 and Fads1) significantly decreased at all-time points compared to the control group. These results suggested that impaired immunity and depressed metabolism under cold stress may be the main cause of the massive cold-stress mortality of M. mutica. This study provides novel insights into the molecular mechanisms underlying mass disease and mortality caused by sudden sharp temperature drop events in M. mutica.

Comparative Analysis of the Growth, Physiological Responses, and Gene Expression of Chinese Soft-Shelled Turtles Cultured in Different Modes

“…The genes EGF16, EREG, TNFSF15, IL4R, GHR, F2R, and ITGA in the PI3K/Akt pathways were significantly less expressed in co-cultured turtles. The cytokine-cytokine receptor interaction pathway is closely related to immunity, and it was demonstrated that cytokine-cytokine receptor interactions were activated in turtles after stress [ 59 , 60 ]. The downregulated number of cytokine and cytokine receptor genes were more intense in co-cultured turtles, and the significant downregulations included CCL4, CCL4L1, CCL4L2, CXCL8, IL4R, CSF3R, IL1R2, TNFSF15, and TNFSF10, which indicates a reduced immune response in co-cultured turtles.…”