缺氧已成为限制水产养殖发展的最关键因素之一。鲤鱼(Carassiusauratus)是中国广泛食用的鱼类,对低氧环境具有优异的耐受性。然而,cru鱼缺氧适应和耐受的分子机制尚不清楚。与对照相比,T-SOD增加,CAT,GSH-Px,T-AOC,ALT,AST活性和MDA,TCHO,和TG含量,低氧胁迫后,TP和ATP含量降低。基于RNA-seq,2479个差异表达(DE)mRNA和60个DEmiRNA,和许多参与HIF信号通路的DEmRNA(HIF-1α,epo,vegfa,andho),厌氧代谢(hk1/hk2,pfk,gapdh,pk,和ldh)和免疫应答(nlrp12,cxcr1,cxcr4,ccr9和cxcl12)在缺氧暴露后显著上调。综合分析发现,预测igfbp1、hsp70和hk2受novel_867、dre-miR-125c-3p/novel_173、dre-miR-181b-5p、和dre-miR-338-5p/dre-miR-17a-3p,分别,MAPK信号通路显著富集DEmiRNAs,FoxO信号通路,和糖酵解/糖异生。表达分析表明,vegfa的mRNA水平,epo,ho,hsp70,hsp90aa.1,igfbp1,ldh,hk1,pfk,pk,gapdh表现出显著的增长,而sdh和mdh在H3h下调,H12h,H24h组与对照组比较。此外,研究发现,hk2是dre-miR-17a-3p的靶标,过表达dre-miR-17a-3p显著降低了hk2的表达水平,而在dre-miR-17a-3p沉默后获得相反的结果。这些结果有助于我们了解cru鱼耐缺氧的分子机制。
Hypoxia has become one of the most critical factors limiting the development of aquaculture. Crucian carp (Carassius auratus) is widely consumed fish in
China, with excellent tolerance to hypoxic environment. However, the molecular mechanisms underlying hypoxia adaptation and tolerance in crucian carp remain unclear. Compared with the control, increased T-SOD, CAT, GSH-Px, T-AOC, ALT, and AST activities and MDA, TCHO, and TG contents, and decreased TP and ATP contents were observed after hypoxia stress. Based on RNA-seq, 2479 differentially expressed (DE) mRNAs and 60 DE miRNAs were identified, and numerous DE mRNAs involved in HIF signaling pathway (hif-1α, epo, vegfa, and ho), anaerobic metabolism (hk1/hk2, pfk, gapdh, pk, and ldh) and immune response (nlrp12, cxcr1, cxcr4, ccr9, and cxcl12) were significantly upregulated after hypoxia exposure. Integrated analysis found that ho, igfbp1, hsp70, and hk2 were predicted to be regulated by novel_867, dre-miR-125c-3p/novel_173, dre-miR-181b-5p, and dre-miR-338-5p/dre-miR-17a-3p, respectively, and targets of DE miRNAs were significantly enriched in MAPK signaling pathway, FoxO signaling pathway, and glycolysis/gluconeogenesis. Expression analysis showed that the mRNA levels of vegfa, epo, ho, hsp70, hsp90aa.1, igfbp1, ldh, hk1, pfk, pk, and gapdh exhibited a remarkable increase, whereas sdh and mdh were downregulated in the H3h, H12h, and H24h groups compared with the control. Furthermore, research found that hk2 is a target of dre-miR-17a-3p, overexpression of dre-miR-17a-3p significantly decreased the expression level of hk2, while the opposite results were obtained after dre-miR-17a-3p silencing. These results contribute to our understanding of the molecular mechanisms of hypoxia tolerance in crucian carp.