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

在脂肪种子萌发过程中，蛋白体相互融合，最终成为中心液泡。分析了蛋白体向液泡的转化过程，重点研究了膜流动系统中的膜融合问题，建立了从蓖麻籽和南瓜籽中分离蛋白体膜和液泡膜的方法，并对膜蛋白的开发进行了研究。在蓖麻籽蛋白体膜中检测到四种主要的膜蛋白(80kD、28kD、26kD、24kD)，这些蛋白在蛋白体向液泡转化的过程中数量减少。南瓜蛋白体膜蛋白主要有5种蛋白(73kD、51kD、32kD、27kD、23kD)。这些膜蛋白在转化过程中也减少了，但在膜上出现了几种新的蛋白(94kD、58kD、16kD)。免疫化学分析表明，80kD和26kD的蓖麻籽蛋白分别与南瓜73kD和32kD蛋白发生交叉反应，表明这两种蛋白具有相似的结构和功能。这些抗体对蛋白质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.