樟树核糖体失活蛋白在种子成熟过程中的动态变化与特性

樟树种子中存在着ｃｉｎｎａｍｏｍｉｎ与ｃａｍｐｈｏｒｉｎ两种新的核糖体失活蛋白，电泳分析与Ｗｅｓｔｅｒｎ杂交结果表明ｃｉｎｎａｍｏｍｉｎ在９、１０、１１月份种子中的含量分别是８．９％，２６．８％和１１．５％，以１０月份种子的含量为最高。ｃａｍｐｈｏｒｉｎ的含量则分别为１．７％，２．５％与４．６％，随着种子的成熟而不断增加。８月份的幼嫩种子中检测不出ｃｉｎｎｍａｍｏｍｉｎ与ｃａｍｐｈｏｒｉｎ．这表明樟树核糖体失活蛋白的表达受到了发育进程的时态调控．樟树叶片中可能不存在ｃｉｎｎａｍｏｍｉｎ与ｃａｍｐｈｏｒｉｎ，即两者的合成似乎具有一定的组织特异性．ｃｉｎｎａｍｏｍｉｎ与ｃａｍｐｈｏｒｉｎ均为糖蛋白。

Dynamic Change and Characterization of Ribosome-Inactivating Proteins during the Maturation of Seed of Cinnamomum camphora

Two types of ribosome-inactivating proteins(RIPs) were found to exist in the seed of Cinnamomum camphora,which termed as cinnamomin and camphorin. After the purification of these two RIPs,their dynamic changes and some properties were investigated in this paper. Nondenaturing polyacrylamide gel eletrophoretic and Western blotting results showed that the content of cinnamomin in the seed of Sept.,Oct. and Nov. was 8. 9 %,26. 8 % and 11. 5 % respectively,among which cinnamomin was maximally synthesized in the seed of Oct. Meanwhile,camphorin content was 1. 7% (Sept),2. 5 % (Oct) and 4. 6% (Nov),gradually increasing with the maturation of seed. These results suggest that the syntheses of cinnamomin and camphorin are regulated by developmental process. In addition,no cinnamomin and camphorin were detected in the leaves,implying that cinnamomin and camphorin are specifically synthesized in the seed. Cinnamomin and camphorin are both glycoproteins,but the carbohydrate content of cinnamomin is 166──fold higher than that of camphorin.