水体pH对中华绒螯蟹幼蟹蜕壳生长及其相关基因表达的影响

为了解养殖水体p H值对中华绒螯蟹(Eriocheir sinensis)蜕壳生长及其相关基因表达的影响,在试验室水槽条件下,设定p H=7、8、9、10(均无水草)为实验组,以种植适量水草(p H值为8.2~9.1)为对照组,研究中华绒螯蟹幼蟹(均重0.43 g±0.09 g)在不同p H值水体中饲养一个蜕壳周期(37 d)的蜕壳生长及其相关基因(蜕皮抑制激素MIH,蜕皮激素受体EcR,维甲类X受体RXR,胰岛素样生长因子IGF2)表达情况。结果显示,对照组河蟹的成活率和增重率均显著高于实验组,其中,p H10的河蟹成活率和增重率最低。荧光定量PCR检测显示,MIH、EcR和RXR基因在不同p H水体的表达存在显著差异,IGF2基因在不同p H水体中的表达无显著差异;不同p H水体幼蟹的增重率与成活率之间存在显著正相关,EcR、RXR与IGF2基因相互间的表达量存在显著正相关,表明这三个基因的表达具有协同作用。通过对成活率、增重率和基因表达的综合分析认为幼蟹生长的最适p H为8~9。

The effect of pH on the molting,growth and related gene expression in juvenile mitten crab,Eriocheir sinensis

In order to investigate the effect of pH on the molting , growth and expression of related genes (MIH, EcR, RXR, IGF2) in juvenile mitten crabs, Eriocheir sinensis, with the average weight of (0.43 ±0.09)g cultured in the in-door experiment closets, tests were conducted with four experimental group of pH =7, 8, 9 and 10 (no water grass) and one control group (water grass) for one inter-molting period (37 days).The results indicated that the survival rate and weight gain in the control group were significantly higher than those in the experimental groups , while the lowest survival rate and weight gain existed in the pH 10 group.The quantitative real-time PCR showed there were significant expression difference in MIH, EcR and RXR genes.Among the different water pH groups , however, there was no significant expres-sion difference in IGF2 gene.Correlation analysis showed that there was significant positive correlation between the weight gain rate and survival rate, and among EcR、 RXR and IGF2 genes, indicating synergistic effects in expression in the three genes.Combining survival rate, weight gain and gene expression , it would have been concluded that the optimal pH was 8 ~9 for juvenile crab.