Glutathione peroxidase (GPX) gene expression can reflect the resilience of the organisms to environmental pressure. Central composite design and response surface methodology are applied to study the effects of temperature (18 – 34 ℃) and salinity (20 – 40) on the expression of GPX gene in four shell color strains of Pinctada martensii under laboratory conditions,. The results show that expression of GPX gene in four shell color strains is first decreased and then increased as temperature and salinity increase; the linear and quadratic effects of temperature on the expression of GPX gene in four shell color strains are highly significant (P < 0.01). The linear effect of salinity is significant on the expression of GPX gene in black shell color strain (P < 0.05). The quadratic effect of salinity in white shell color strain is significant (P < 0.05), and is highly significant in black, red, yellow shell color strains (P < 0.01). The interactive effect between temperature and salinity is significant in black, red, yellow shell color strains (P < 0.05), and the effect of temperature is greater than the effect of salinity. By response surface analysis and optimization, the expression of GPX gene has a peak value change in the suitable range of temperature and salinity, and the white, black, red, yellow shell color stains of Pinctada martensii with the optimal (low) expression value of 0.072, 0.065, 0.057, 0.065, and the desirability of 100%, 100%, 97%, 100%, under the condition of temperature and salinity group (21.4 ,℃30.1), (24.8 , 28.5), (25.2℃ , 30.5), (25.1℃ , 29.7)℃ , respectively. The model equation of GPX gene expression towards to temperature and salinity is established, with R2 ranging from 0.971 3 to 0.995 8, adjusted R2 from 0.942 6 to 0.991 5 and predictive R2 from 0.713 9 to 0.968 0 in all four color shell strains, indicating that the model is very satisfactory for goodness of fit and can be applied for prediction of the expression of GPX gene expression level under different combinations of temperature and salinity in four shell color strains of P. martensii.%谷胱甘肽过氧化物酶（GPX）基因表达可反映生物对环境压力的抗逆能力。采用中心复合设计和响应曲面分析法研究不同温度（18~34℃）、盐度（20~40）对4种壳色马氏珠母贝 GPX 基因表达量的影响。结果表明，马氏珠母贝4种壳色群体 GPX 基因表达量随着温度和盐度的升高，呈现先降低后升高的趋势。温度的一次、二次效应对4种壳色马氏珠母贝 GPX 基因表达的影响有统计学意义（P <0.01）。盐度的一次效应仅对黑壳色马氏珠母贝 GPX 基因表达影响有统计学意义（P <0.05）；盐度的二次效应对白壳色马氏珠母贝 GPX 基因表达的影响有统计学意义（P <0.05），对黑、红、黄壳色马氏珠母贝 GPX 基因表达的影响有统计学意义（P <0.01）。温盐协同效应对黑、红、黄壳色马氏珠母贝 GPX 基因表达的影响有统计学意义（P <0.05），且温度的效应大于盐度效应。经响应曲面分析法和优化，得到马氏珠母贝的 GPX 基因表达量在适宜的温度、盐度范围内呈峰值变化，白、黑、红、黄等4种壳色马氏珠母贝分别在（21.4℃，30.1）、（24.8℃，28.5）、（25.2℃，30.5）、（25.1℃，29.7）等温盐度组合条件下达到最优（低）值（0.072、0.065、0.057、0.078），满意度分别为100%、100%、97%、100%。所建立回归模型方程的决定系数 R2范围为0.9713~0.9958，校正决定系数 R2范围为0.9426~0.9915，预测决定系数 R2范围为0.7139~0.9680，模型拟合度高，模型恰当，可用于预测温度、盐度对4种壳色马氏珠母贝 GPX基因表达量的影响。
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