Integrated analysis of circRNA-miRNA-mRNA ceRNA network responses to heat stress in rainbow trout (Oncorhynchus mykiss) liver

With the intensification of global warming, rainbow trout is suffering from varying degrees thermal stimulation, heat stress may cause pathological signs or diseases by reducing the immune roles and then lead to mass mortality, so high temperatures severely restrict the development of its aquaculture. Understanding the molecular regulation mechanism of rainbow trout under heat stress is used to take measures to relieve symptoms. We performed multiple transcriptomic analysis of liver tissues from rainbow trout under heat stress (24 °C) and control conditions (18 °C) to identify circRNAs, miRNAs and mRNAs. Changes of non-specific immune parameters revealed that strong stress response of rainbow trout is caused in 24 °C. A total of 324 DEcircRNAs, 105 DEmiRNAs, and 1885 DEmRNAs were identified from six libraries, and ceRNA regulatory network is constructed. 301 circRNA–miRNA and 51 miRNA–mRNA negative correlation pairs were screened from ceRNA regulatory network, and predicted three regulatory correlation pairs that novel_circ_003889 - novel-m0674-3p - hsp90ab1, novel_circ_002325 - miR-18-y - HSPA13 and novel_circ_002446 - novel-m0556-3p - hsp70. Some genes involved in metabolic process, biological regulation or response to stimulus are highly induced at high temperatures. Several important pathways involved in heat stress were characterized, such as Protein processing in endoplasmic reticulum (ER), Estrogen signaling pathway, HIF-1 signaling pathway, etc. These results extend our understanding of the molecular mechanisms of heat stress response and expected to provide a novel insight into develop strategies for relieve heat stress. Overall design: liver tissues of rainbow trout under heat stress (24?, HS, n=3) and control (18?, CG, n=3) conditions to identify induced miRNAs