【摘要】 【目的】探究家蚕Bombyx mori胚胎发育早期卵内糖代谢与滞育的关系。【方法】以家蚕二化性品种"秋丰"活化越年卵为材料,一部分于17℃暗催青,孵化后常规饲养,制备非滞育命运卵(ND);另一部分于25℃明催青,孵化后常规饲养,制备滞育命运卵(DD),再用盐酸溶液处理部分DD卵制备即时浸酸卵(IA)。在卵产下或浸酸后0, 2, 6, 12, 24, 48, 72和96 h分别取样,利用qRT-PCR测定家蚕卵中己糖激酶(hexokinase, HK)、磷酸果糖激酶(phosphofructokinase, PFK)、山梨醇脱氢酶(sorbitol dehydrogenase, SDH)、磷酸烯醇式丙酮酸羧激酶(phosphoenolpyruvate carboxykinase, PEPCK)和海藻糖酶(trehalase, TRE)5种糖代谢相关酶基因的mRNA表达水平,利用紫外-可见分光光度法测定家蚕卵中这5种酶的活性。【结果】家蚕糖酵解途径关键酶己糖激酶(BmHK)和磷酸果糖激酶(BmPFK),以及糖分解代谢关键酶山梨醇脱氢酶(BmSDH-1)和海藻糖酶(BmTRE)在ND和IA中的mRNA水平和活性均普遍高于在DD中的;而糖异生途径相关的磷酸烯醇式丙酮酸羧激酶(BmPEPCK)在DD中的mRNA水平和活性均高于在ND和IA中的。【结论】结果提示,DD因胚胎滞育的需要,胚胎发育早期卵内糖代谢以能量和物质的贮存为主;而ND和IA由于胚胎发育进程较快,糖代谢以物质分解代谢为主。本研究初步揭示了家蚕卵内糖代谢与滞育的关系,有助于更好地理解家蚕滞育的分子机制。更多还原

【Abstract】 【Aim】 To clarify the relationship between carbohydrate metabolism and diapause during the early embryonic developmental stage in Bombyx mori. 【Methods】 The activated hibernating eggs of bivoltine B. mori strain Qiufeng were used as materials. Some were incubated under 17℃ in darkness and fed normally to produce the non-diapause-destined eggs(ND), and others were incubated under 25℃ in natural circadian rhythm and fed normally to produce the diapause-destined eggs(DD), part of which were further treated with HCl solution to produce the immediately acid-treated eggs(IA). Samples were collected at 0, 2, 6, 12, 24, 48, 72, and 96 h, respectively, after oviposition or acid treatment. The mRNA levels of genes of five carbohydrate metabolism-related enzymes including hexokinase(HK), phosphofructokinase(PFK), sorbitol dehydrogenase(SDH), phosphoenolpyruvate carboxykinase(PEPCK) and trehalase(TRE) in B. mori eggs were detected by qRT-PCR, and the activities of the five enzymes in B. mori eggs were assayed by ultraviolet visible spectrophotometry. 【Results】 The overall mRNA levels and activities of the key enzymes of glycolysis,hexokinase(BmHK) and phosphofructokinase(BmPFK), and the key enzymes of glycometabolism, sorbitol dehydrogenase(BmSDH-1) and trehalase(BmTRE), in ND and IA of B. mori were higher than those in DD, while the mRNA levels and activities of phosphoenolpyruvate carboxykinase(BmPEPCK) related to gluconeogenesis in DD were higher than those in ND and IA. 【Conclusion】 The results suggest that in the early embryonic developmental stage of DD, carbohydrate metabolism is mainly towards energy and material storage for diapause, while in ND and IA, carbohydrate metabolism is mainly towards material catabolism due to fast embryonic development. This study has preliminarily uncovered the relationship between carbohydrate metabolism and diapause of B. mori, being beneficial to better understand the molecular mechanisms of diapause of B. mori.更多还原