Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Key Laboratory of Fish Applied Biology and Aquaculture in North China, Liaoning Province, College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China.
Key Laboratory of Mariculture & Stock Enhancement in North China's Sea, Ministry of Agriculture and Rural Affairs, Key Laboratory of Fish Applied Biology and Aquaculture in North China, Liaoning Province, College of Fisheries and Life Science, Dalian Ocean University, Dalian 116023, China.
Comp Biochem Physiol B Biochem Mol Biol. 2020 Jun;243-244:110437. doi: 10.1016/j.cbpb.2020.110437. Epub 2020 Apr 1.
Salinity is an important abiotic factor for aquatic organisms. In fish, changes in salinity affect physiological responses and alter the immune system. Takifugu rubripes is an important economic marine fish, and mechanisms of T. rubripes adaptation to salinity changes need to be further documented. In this study, a transcriptome sequencing technique was used to analyse genes that were differentially expressed in the T. rubripes gill after low-salinity stress for 30 d, and differential gene expression was further validated by quantitative real-time PCR (qPCR). After assembly, 385 differentially expressed genes (DEGs) were identified, including 182 upregulated genes and 203 downregulated genes. The DEGs were assigned to Gene Ontology (GO) classes with a total of 1647 functional terms. Most DEGs were assigned to biological process (984; 59.8%) followed by molecular function (445; 27.0%) and cellular component (218; 13.2%). Further KEGG analysis allocated 385 DEGs to 95 KEGG pathways. After q-value correction, 7 pathways (Glycolysis/Gluconeogenesis; Biosynthesis of amino acids; Carbon metabolism; Fructose and mannose metabolism; Pentose phosphate pathway; Metabolism of xenobiotics by cytochrome P450; and Glycine, serine and threonine metabolism) remained significant. qPCR results indicated that the transcripts of six selected genes sharply increased after 30 d of low-salinity stress. Low-salinity stress obviously increased SLC39A6, SLC5A9, NKAα1, CYP1A1, CYP1B1, and GSTA expression. In contrast, the genes encoding Aldoaa, GPI, FBP2 and GAPDH exhibited downregulation. In addition, three solute carrier (SLC) genes selected from the DEGs were further studied for differential expression patterns after low-salinity exposure, and the results showed that the SLCs were upregulated in T. rubripes after 72 h of low-salinity exposure. This investigation provides data for understanding the molecular mechanisms of fish responses to low-salinity stress and provides a reference for rationally setting salinity levels in aquaculture.
盐度是水生生物的一个重要非生物因素。在鱼类中，盐度的变化会影响生理反应并改变免疫系统。红鳍东方鲀是一种重要的经济海洋鱼类，需要进一步研究其适应盐度变化的机制。在这项研究中，使用转录组测序技术分析了红鳍东方鲀鳃在低盐胁迫 30 天后差异表达的基因，并通过定量实时 PCR (qPCR)进一步验证了差异基因表达。组装后，共鉴定出 385 个差异表达基因 (DEGs)，包括 182 个上调基因和 203 个下调基因。这些 DEGs 被分配到基因本体 (GO) 类别，共有 1647 个功能术语。大多数 DEGs 被分配到生物过程 (984; 59.8%)，其次是分子功能 (445; 27.0%)和细胞成分 (218; 13.2%)。进一步的 KEGG 分析将 385 个 DEGs 分配到 95 个 KEGG 途径。经过 q 值校正，有 7 条途径 (糖酵解/糖异生; 氨基酸生物合成; 碳代谢; 果糖和甘露糖代谢; 戊糖磷酸途径; 细胞色素 P450 介导的外源化合物代谢; 甘氨酸、丝氨酸和苏氨酸代谢) 仍然显著。qPCR 结果表明，低盐胁迫 30 天后，6 个选定基因的转录物急剧增加。低盐胁迫明显增加了 SLC39A6、SLC5A9、NKAα1、CYP1A1、CYP1B1 和 GSTA 的表达。相反，编码 Aldoaa、GPI、FBP2 和 GAPDH 的基因则下调。此外，还从 DEGs 中选择了三个溶质载体 (SLC) 基因进一步研究其在低盐暴露后的差异表达模式，结果表明，在低盐暴露 72 小时后，SLCs 在红鳍东方鲀中上调。这项研究为了解鱼类对低盐胁迫的反应的分子机制提供了数据，并为水产养殖中合理设置盐度水平提供了参考。
