Environmental changes in intensive aquaculture commonly lead to hypoxic stress for cultured largemouth bass (Micropterus salmoides). To better to understand the hypoxic stress response mechanisms, the miRNA expression profiles of the livers of largemouth bass exposed for 24 h to three different dissolved oxygen levels (7.0 ± 0.2 mg/L as control, 3.0 ± 0.2 mg/L and 1.2 ± 0.2 mg/L) were compared. In this study, a total of 266 known miRNAs were identified, 84 of which were differentially expressed compared with the control group. Thirteen of the differentially expressed miRNAs (miR-15b-5p, miR-30a-3p, miR-133a-3p, miR-19d-5p, miR-1288-3p, miR456, miR-96-5p, miR-23a-3p, miR-23b-5p, miR-214, miR-24, miR-20a-3p, and miR-2188-5p) were significantly enriched in VEGF signaling pathway, MAPK signaling pathway, and phosphatidylinositol signaling system. These miRNAs were significantly downregulated during stress, especially after a 4-h exposure to hypoxia. In contrast, their target genes (vegfa, pla2g4a, raf1a, pik3c2a, clam2a, inpp1, pi4k2b, mtmr14, ip6k, itpkca, map3k7, and Jun) were significant upregulated after 4 h of hypoxic stress. Moreover, two potential hypoxia-tolerance signal transduction pathways (MAPK signaling pathway and phosphatidylinositol signaling system) were revealed, both of which may play important roles in responding to acute hypoxic stress. We see that miRNAs played an important role in regulating gene expression related to physiological responses to hypoxia.

集约化养殖的环境变化通常导致养殖的大嘴鲈（Micropterus salmoides）的低氧胁迫）。为了更好地了解低氧应激反应机制，大口黑鲈肝脏的miRNA表达谱在24小时内暴露于三种不同的溶解氧水平（对照组为7.0±0.2 mg / L，3.0±0.2 mg / L和1.2±0.2进行比较。在这项研究中，总共鉴定出266种已知的miRNA，其中84种与对照组相比差异表达。十三种差异表达的miRNA（miR-15b-5p，miR-30a-3p，miR-133a-3p，miR-19d-5p，miR-1288-3p，miR456，miR-96-5p，miR-23a-3p ，miR-23b-5p，miR-214，miR-24，miR-20a-3p和miR-2188-5p）在VEGF信号通路，MAPK信号通路和磷脂酰肌醇信号传导系统中显着丰富。这些miRNA在压力下显着下调，尤其是在缺氧4小时后。相反，缺氧应激4小时后，菜豆，pla2g4a，raf1a，pik3c2a，clam2a，inpp1，pi4k2b，mtmr14，ip6k，itpkca，map3k7和Jun）显着上调。此外，揭示了两个潜在的耐缺氧信号转导途径（MAPK信号传导途径和磷脂酰肌醇信号传导系统），这两个途径在应对急性低氧应激中均可能起重要作用。我们看到，miRNA在调节与缺氧的生理反应有关的基因表达中起着重要作用。