Cell Biological Studies on Protein Body-Vacuole Transformation in Germinating Castor Bean Seedlings.

在种子萌发过程中，蛋白体相互融合，最终形成中央液泡。本文分析了蛋白体向液泡转化的过程，特别是膜流系统中膜融合的过程，建立了蓖麻籽和南瓜籽蛋白体膜和液泡膜的分离方法，并对膜蛋白的发育进行了研究。在蓖麻籽蛋白体膜上检测到4种主要的膜蛋白（80 kD、28 kD、26 kD、24 kD），在蛋白体向液泡转化过程中，这些蛋白的含量逐渐减少。在南瓜蛋白体膜上发现5种主要蛋白质（73 kD、51 kD、32 kD、27 kD、23 kD）。这些膜蛋白在转化过程中也有所减少，而在膜上出现了几个新的蛋白（94 kD，58 kD，16 kD）。免疫化学分析表明，蓖麻籽80 kD和26 kD蛋白与南瓜73 kD和32 kD蛋白具有交叉反应，表明这两种蛋白具有相似的结构和功能。这些抗体对蛋白体膜融合的影响正在实验中。

Protein bodies are fused with each other and become finally a central vacuole during germination of fatty seed. We have analyzed the transfomation of protein bodies to vacuoles, especially focused on membrane fusion in membrane flow system.Methods for isolation of protein body membrane and vacuolar membrane from castor bean and pumpkin seed were established and the development of membrane proteins was studied. Four main membrane proteins (80 kD, 28 kD, 26 kD, 24 kd) were detected in protein body membrane from castor bean seed and amounts of these proteins were decreased during transformation of protein bodies to vacuoles. On the other hand, 5 main proteins (73 kD, 51 kD, 32 kD, 27 kD, 23 kD) were found in pumpkin protein body membrane. These membrane proteins were also decreased during the transformation whereas several new proteins (94 kD, 58 kD, 16 kD) appear in the membrane. Immunochemical analysis show that castor bean 80 kD and 26 kD were crossreacted with pumpkin 73 kD and 32 kD, suggesting that these proteins have similar structure and functions.We have prepared monospecific antibodies against these membrane proteins from pumpkin seed. The effect of these antibodies on fusion of protein body membrane are under experiments.