红鳍东方鲀AFP、CIRP、HMGB1和YB-1基因对低温胁迫的响应

Response of AFP, CIRP, HMGB1 and YB-1 gene of Takifugu rubripes to low-temperature stress

中文关键词: 红鳍东方鲀  低温胁迫  AFP  CIRP  HMGB1  YB-1  荧光定量PCR

英文关键词: Takifugu rubripes  Low-temperature stress  AFP  CIRP  HMGB1  YB-1  Quantitative real-time PCR

中文摘要:

      鱼类的生长和繁殖受环境条件的调节，冬季的低温会给红鳍东方鲀(Takifugu rubripes)产业带来不利影响。为研究红鳍东方鲀耐低温机制，本研究利用实时荧光定量PCR技术，分析抗冻蛋白(AFP)基因、冷诱导RNA结合蛋白(CIRP)基因、高速迁移蛋白家族蛋白(HMGB1)基因、Y-box结合蛋白(YB-1)基因在不同温度条件下(18℃、13℃、8℃和5℃)，在红鳍东方鲀的肝、脾、肾、脑、心、肠、肌肉、性腺和皮肤中的表达情况。结果显示，AFP基因呈广泛性表达，在肌肉中表达量最高(P<0.05)，随着温度的降低，各组织中AFP基因的表达量基本呈显著升高的趋势，在5℃组达到最高值，显著高于对照组(P<0.05)。CIRP基因在肌肉中表达量最高(P<0.05)，随着温度的降低，各组织中CIRP基因的表达量的升降程度有所不同，在肝、肾、脑、心、肠、皮肤中的表达量呈先升高后降低再升高的趋势，在脾、肌肉和性腺中表达量呈上升趋势。HMGB1基因在肌肉中表达量最高(P<0.05)，在脑、心、肝和皮肤中也有较高的表达量；随着温度的降低，除肝脏外，各组织中HMGB1基因的表达量基本呈先升高后降低的趋势，并在8℃组达到最大值，显著高于其他各组(P<0.05)。YB-1基因在肌肉中表达量最高(P<0.05)，在其他组织中表达量较低；随着温度的降低，大部分组织中(脑、心、肠、肾、肝、肌肉和脾)表达量呈先升高后降低再升高的趋势，在8℃组达到最小值(P<0.05)。以上结果表明，4种基因表达水平因组织、温度的不同而不同，反映了这4种基因的功能特异性；在低温胁迫下，4种基因积极响应，表达量均发生不同程度的变化，表明4种基因在红鳍东方鲀低温环境适应中可能具有潜在的重要作用。另外，从表达变化规律来看，8℃可能是红鳍东方鲀应对低温胁迫的关键调控点，过低的温度会造成其调控紊乱，这可为研究红鳍东方鲀低温应答调控机制提供相关依据。

英文摘要:

      Environmental conditions regulate the growth and reproduction of fish. The increase in sea temperature during winter may have adverse effects on Takifugu rubripes. To study the mechanism of low-temperature tolerance of T. rubripes, the expression of antifreeze protein (AFP) gene, cold-induced RNA binding protein (CIRP) gene, high mobility group protein box-1 (HMGB1) gene, and Y-box binding protein (YB-1) gene in the liver, spleen, kidney, brain, heart, intestine, muscle, gonad, and skin tissues of T. rubripes obtained from different temperatures (18℃, 13℃, 8℃, and 5℃) was analyzed by quantitative real-time PCR. The results showed that the AFP gene was widely expressed in tissues, with the highest expression in the muscle (P<0.05). With the decrease in temperature, the expression of the AFP gene in each tissue showed a significant increasing trend, reaching the highest value in the 5℃ group. The expression of the CIRP gene was the highest in the muscle (P<0.05). With a decrease in temperature, the trend of CIRP gene expression in various tissues was different. The CIRP gene expression levels of liver, kidney, brain, heart, intestine, and skin showed a trend of initial increase, followed by a decrease, and then an increase. The expression levels in the spleen, muscle, and gonads showed an upward trend, reaching the highest value in the 5℃ group. The expression of the HMGB1 gene was the highest in muscle (P<0.05), followed by that in the brain, liver, heart and skin. As the temperature decreased, the expression of the HMGB1 gene in all tissues except the liver increased first and then decreased, and reached the maximum value in the 8℃ group, which was significantly higher than that of the other groups (P<0.05). The expression of the YB-1 gene was the highest in the muscle (P<0.05), with the lowest expression level in other tissues. As the temperature decreased, the expression level of most tissues (brain, heart, intestine, kidney, liver, muscle, and spleen) increased first, then decreased, and then increased, reaching the minimum value in the 8℃ group (P<0.05). These results show that the expression levels of the four genes are different at different temperature, reflecting the functional specificity of these four genes. Under low-temperature stress, these genes responded positively. Their expression changed to varying degrees, suggesting that the four genes may have potentially important roles in the adaptation of T. rubripes to low temperatures. In addition, by analyzing the law of gene expression, 8℃ may be the key regulatory point for T. rubripes to deal with low-temperature stress. Too low temperature may cause its regulation disorder. The results of this study can provide a relevant basis for studying the regulation mechanism of the low-temperature response of T. rubripes.