MAPKs信号通路抑制剂对红耳龟渗透压调节基因表达的影响

Effect of MAPKs Signaling Pathway Inhibitors on the Expression of Osmotic Pressure Regulation-Related Genes in Trachemys scripta elegans

为了解丝裂原活化蛋白激酶(MAPKs)信号通路对盐度耐受下红耳龟Trachemys scripta elegans渗透压相关调节基因的影响,本研究应用JNK、ERK、p38MAPK抑制剂处理红耳龟后,置于淡水及5‰盐度水环境中,24 h后取肾脏组织,应用实时荧光定量PCR方法检测渗透压调节相关基因的mRNA相对表达量。结果表明,盐度环境下红耳龟肾脏中水通道蛋白3(AQP3)、热休克蛋白70(HSP70)、醛糖还原酶(AR)、糖皮质激素诱导蛋白激酶(SGK1)、肌醇转运蛋白(SMIT)的mRNA相对表达量显著升高,与淡水组差异显著(P<0.05)。不同浓度的JNK、ERK、p38MAPK抑制剂均能下调HSP70、AR的mRNA相对表达量,与未用抑制剂处理的5‰盐度组相比,差异显著(P<0.05);此外,ERK、p38MAPK抑制剂显著降低了AQP3 mRNA相对表达量(P<0.05),JNK、p38MAPK抑制剂显著降低了SMIT mRNA相对表达量(P<0.05);SGK1 mRNA相对表达量随p38MAPK抑制剂浓度的增加呈下降趋势,且在高浓度(25 mg·kg^(-1))下的表达量最低(P<0.05)。研究结果表明,红耳龟在适应半咸水过程中,MAPKs信号通路对渗透压有一定的调节作用。

In order to understand the effect of MAPKs signaling pathway on osmotic pressure regulation-related genes in saline-tolerant red-eared slider(Trachemys scripta elegans),three inhibitors(JNK,ERK and p38MAPK)were applied,and then the red-eared sliders were placed in freshwater and salinity water(5‰).After 24 h,the kidney tissue was extracted.The mRNA relative expression levels of osmotic pressure regulation-related genes were detected by real-time fluorescence quantitative PCR.The results showed that compared to the freshwater group,the mRNA relative expression levels of AQP3,HSP70,AR,SGK1 and SMIT in red-eared sliders in salinity water were significantly increased(P<0.05).By contrast,the presence of JNK,ERK and p38MAPK inhibitors significantly decreased the expression of HSP70 and AR(P<0.05).In addition,both ERK and p38MAPK inhibitors could significantly reduce the expression of AQP3(P<0.05).JNK and p38MAPK inhibitors significantly decreased the expression of SMIT(P<0.05).The relative expression level of SGK1 mRNA decreased with the increasing concentration of p38MAPK inhibitor and reached the lowest at the concentration of 25 mg·kg^(-1).This study suggests that MAPKs signaling pathway can regulate osmotic pressure of T.s.elegans in adapting to brackish water.