为研究夏季暴雨导致的养殖池塘盐度变化对仿刺参(Apostichopus japonicus)生理的影响,在实验室内模拟野外盐度变化,采用半定量RT-PCR的方法研究了其hsp70、hsp90a及hsp90b基因的表达。实验中,盐度先以每6h降2.5的速度由30降至20;保持96h后,再以同样的速度由20升至30,随后在盐度为30条件下保持96h。在盐度变化过程中随机取样。hsp70和hsp90b基因在盐度降至20后表达量开始显著升高(P〈0.05),hsp90a基因在盐度降至22.5时表达量开始显著升高(P〈0.05);但保持在盐度为20条件下,3个基因的表达量均逐渐降低至初始值。在之后的盐度升高及恢复阶段,3个基因表达量均有先升高后降低的趋势,表明hsp70、hsp90a和hsp90b基因是仿刺参在盐度胁迫下的重要响应因子。
The expression of hsp70,hsp90a and hsp90b genes in sea cucumber(apostichopus japonicus Selenka) were studied in a simulated field salinity decrease after a heavy rainfall in summer.Salinity firstly decreased gradually from 30 to 20 at a rate of 2.5 every 6 h,and then was maintained at 20.After 96 h at the low salinity(20),salinity was increased gradually to 30 at a rate of 2.5 every 6 h,and then was maintained at 30 for 96 h.Results showed that expressions of hsp70,hsp90a and hsp90b genes all increased after salinity decrease,led to the maximum levels at the lowest salinity,and then dropped to the original level after 72 h at low-salinity exposure.Similarly,the expression of these three genes in sea cucumber increased with the salinity increase,and decreased to the original level after 72 h at low-salinity exposure.Compared to the second salinity fluctuation,the gene expressions were lower than those of the first salinity fluctuation,which might be caused by energy budget.In this study the expression of hsp90a and hsp90b genes was similar to hsp70 gene’s expression,and the upregulated expression of hsp90s also could be regarded as the physiologic adaptation of Apostichopus japonicus to environmental stresses.