甜瓜子叶发育过程中蛋白质水平和氨同化酶活性变化

甜瓜子叶发育过程中蛋白质水平和氨同化酶活性变化 Change of Level of Protein and Activities of Enzymes Involved in Ammonium Assimilation during Development of Melon （Cucumis melo L. ） Cotyledons 欧吉权 OU Ji-quan 1 2 first-author 魏国威 WEI Guo-wei 1 2 张楚富 ZHANG Chu-fu 1 2 张吉 ZHANG Ji 1 2 林清华 LIN Qing-hua 1 2 武汉大学生命科学学院/植物发育生物学教育部重点实验室 武汉大学生命科学学院/植物发育生物学教育部重点实验室 College of Life Sciences,Wuhan University/Key Laboratory of MOE for Plant Developmental Biology College of Life Sciences,Wuhan University/Key Laboratory of MOE for Plant Developmental Biology 武汉大学生命科学学院/植物发育生物学教育部重点实验室,湖北,武汉,430072 武汉大学生命科学学院/植物发育生物学教育部重点实验室,湖北,武汉,430072 测定了甜瓜种子萌发和子叶发育过程中谷氨酰胺合成酶 （GS）、依赖于NADH的谷氨酸合酶 （NADH GOGAT）、依赖于NADH的谷氨酸脱氢酶 （NADH GDH）等酶的活性变化以及种子萌发时可溶性蛋白水平的变化 .在有氮或无氮下 ,在子叶刚出土时GS和NADH GOGAT活性较低 ,随着子叶的发育 ,这两种酶的活性升高 ,两者分别于第 7天和第 5天达到最高 ,其后活性逐步降低 .但是NADH GDH呈现出相反的变化 ,在子叶发育的前期阶段其活性低 ,而后逐步升高 .可溶性蛋白的含量随着子叶的发育而逐步降低 .外源氮的加入对蛋白质水平和酶的活性具有小的正面影响 The activities of glutamine synthetase （GS）,NADH-dependent glutamate synthase （NADH-GOGAT）, NADH-dependent glutamate dehydrogenase （NADH-GDH）,and the level of the soluble protein were determined during cotyledon development in melon （Cucumis melo L.）. At the condition of the seedlings grown in the ammonium-medium or ammonium-free medium, the activities of GS and NADH-GOGAT were high at the early stages of the developmental cotyledons, and were the highest at day 7 and day 5,respectively, after sowing, but their activities subsequently decreased at late stages of seedling growth. In contrast, the activity of NADH-GDH was low at first stages of cotyledon development, and then gradually increased. The soluble protein declined as the cotyledon development. Exogenous nitrogen had a slight positive effect on protein level and these enzyme activities. 谷氨酰胺合成酶 谷氨酸合酶 谷氨酸脱氢酶 发育 甜瓜 glutamine synthetase NADH-dependent glutamate synthase NADH-dependent glutamate dehydrogenase development melon （Cucumis melo L.） S652 国家自然科学基金资助项目 （ 3 0 2 70 13 0 ） 2003-04-01 2021-04-01 4