Takase Tomomasa, Yanagawa Yuki, Komatsu Setsuko, Nakagawa Hiroki, Hashimoto Junji
Department of Bioproduction Science, Faculty of Horticulture, Chiba University, Matsudo, Chiba 271-8510, Japan.
J Plant Res. 2003 Dec;116(6):469-75. doi: 10.1007/s10265-003-0122-6. Epub 2003 Oct 1.
To understand the cell cycle process in plants, we searched for proteins that quantitatively change during the cell cycle in suspension-cultured rice ( Oryza sativa L.) cells. The proteins were analyzed by a two-dimensional polyacrylamide gel electrophoresis image-analysis system. We detected 11 proteins that quantitatively changed during the cell cycle, among which beta-tubulins and a calreticulin-like protein were identified. The amounts of beta-tubulin proteins were low in the M phase and high in the G1 phase. In contrast, mRNAs for two of the three types of beta-tubulin were high in the M phase of the cell cycle. The addition of protease inhibitors MG132 or E64d to the cells decreased the beta-tubulin proteins during 24 h, suggesting that beta-tubulin proteins are degraded in vivo by proteases other than those whose activities are inhibited by MG132 or E64d.
为了解植物细胞周期进程，我们在悬浮培养的水稻（Oryza sativa L.）细胞中寻找在细胞周期中发生定量变化的蛋白质。通过二维聚丙烯酰胺凝胶电泳图像分析系统对这些蛋白质进行分析。我们检测到11种在细胞周期中发生定量变化的蛋白质，其中鉴定出了β-微管蛋白和一种类钙网蛋白。β-微管蛋白在M期含量低，在G1期含量高。相反，三种类型的β-微管蛋白中的两种的mRNA在细胞周期的M期含量高。向细胞中添加蛋白酶抑制剂MG132或E64d在24小时内会使β-微管蛋白减少，这表明β-微管蛋白在体内会被除MG132或E64d抑制活性的蛋白酶之外的其他蛋白酶降解。
