Rainbow trout are typical cold-water fish species. However, with the intensification of global warming, high temperatures have severely restricted the development of aquaculture during the summer. Understanding the molecular regulatory mechanisms of rainbow trout responses to heat stress will be beneficial for alleviating heat stress-related damage. In this study, we performed RNA-seq of liver tissues from rainbow trout under heat stress (24 °C) and control conditions (18 °C) to identify lncRNAs and target genes by strand-specific library. Changes in nonspecific immune parameters revealed that a strong stress response occurred in rainbow trout at 24 °C. More than 658 million filtered reads and 5916 lncRNAs were identified from six libraries. A total of 927 novel lncRNAs were identified, and 428 differentially expressed lncRNAs were screened with stringent thresholds. The RNA-seq results were verified by RT-qPCR. In addition, a regulatory network of lncRNA-mRNA functional interactions was constructed, and the potential antisense, cis and trans targets of lncRNAs were predicted. GO and KEGG enrichment analyses showed that many target genes involved in maintenance of homeostasis or adaptation to stress and stimuli were highly induced under heat stress. Several regulatory pathways were also found to be involved in heat stress, including the thyroid hormone signaling pathway, the PI3K-Akt signaling pathway, and the estrogen signaling pathway, among others. These results broaden our understanding of lncRNAs associated with heat stress and provide new insights into the lncRNA mediated regulation of the rainbow trout heat stress response.

虹鳟鱼是典型的冷水鱼类。然而，随着全球变暖的加剧，夏季的高温严重限制了水产养殖的发展。了解虹鳟鱼对热应激反应的分子调控机制将有助于减轻与热应激相关的伤害。在这项研究中，我们在热应激（24°C）和控制条件（18°C）下对虹鳟鱼肝组织进行RNA测序，以通过链特异性文库鉴定lncRNA和靶基因。非特异性免疫参数的变化表明，虹鳟鱼在24°C时发生了强烈的应激反应。从六个文库中鉴定出超过6.58亿个过滤的读数和5916个lncRNA。总共鉴定出927个新颖的lncRNA，用严格的阈值筛选了428个差异表达的lncRNA。RNA-seq结果通过RT-qPCR验证。另外，构建了lncRNA-mRNA功能相互作用的调控网络，并预测了lncRNA的潜在反义，顺式和反式靶标。GO和KEGG富集分析表明，在热胁迫下，许多与维持体内稳态或对压力和刺激的适应有关的靶基因被高度诱导。还发现了几种与热应激有关的调节途径，包括甲状腺激素信号传导途径，PI3K-Akt信号传导途径和雌激素信号传导途径等。