二化性家蚕滞育过程中谷胱甘肽S-转移酶活性的变化

二化性家蚕卵以25℃和15℃催青,可分别诱导成虫产下子代滞育和非滞育卵,而即时浸酸和5℃左右的低温处理可以分别阻止和解除胚胎滞育。利用1-氯-2,4-二硝基苯(CDNB)显色法测定了经上述处理后的胚胎滞育过程中谷胱甘肽S-转移酶(glutathione S-transferase,GST)的活性,结果表明:胚胎发育后期的蚕卵经25℃催青,卵中的GST活性显著高于15℃催青蚕卵;蚕卵即时浸酸未显著改变胚胎滞育发动阶段蚕卵中的GST活性;5℃低温处理显著提高了滞育卵中的GST活性,但是未能显著改变即时浸酸卵的GST活性。上述结果表明,蚕卵中的GST活性变化与二化性家蚕胚胎滞育诱导和解除密切相关。

Variation of Glutathione S-transferase in Eggs of Bivoltine Strain (Bombyx mori) During Diapause Process

Bivoltine strain of Bombyx mori produces diapause and non-diapause eggs when embryogenesis of the parental eggs was induced at 25℃ and 15℃, respectively. Meanwhile, diapause status can be prevented and terminated by immediate hydrochloric acid treatment and low temperature treatment around 5℃, respectively. In this study, effects of the above treatments on activity of glutathione S-transferase (GST, EC 2.5.1.18) in eggs during diapause process was determined by using 1-chloro-2,4-dinitrobenzene (CDNB) as the color displaying agent. It was discovered that, when eggs at their late embryonic stage were incubated at 25℃, the eggs' GST activity was significantly higher than that incubated at 15℃. GST activity in eggs was not significantly changed by immediate hydrochloric acid treatment at the diapause initiation phase. During the 5℃ chilling, activity of GST in diapause eggs was significantly enhanced while that in diapause eggs with immediate hydrochloric acid treatment was not changed significantly. The above results suggest that variation of GST activity in eggs is closely related to embryonic diapause induction and termination in bivoltine strain of Bombyx mori.