Tobacco mosaic virus movement protein-mediated protein transport between trichome cells.
Tobacco mosaic virus movement protein-mediated protein transport between trichome cells.
复制标题
烟草花叶病毒运动蛋白介导毛状体细胞之间的蛋白质运输。
DOI：
10.1105/tpc.7.12.2069
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Zambryski,P
中科院分区：
文献类型：
--
作者：
Waigmann,E;Zambryski,P
烟草花叶病毒运动蛋白（TMV MP）是烟草花叶病毒通过胞间连丝在植物细胞间传播所必需的。胞间连丝是连接植物细胞的细胞质桥梁，通常将分子扩散限制为分子量高达1 kD的小分子和代谢物。在这里，我们描述的功能特性的烟草腺毛胞间连丝，并分析其与TMV MP的相互作用。毛状体构成线性细胞系统并提供可预测的运动途径。它们的胞间连丝在功能上不同于其他植物细胞类型中的胞间连丝;它们允许分子量高达7 kD的葡聚糖在细胞间扩散，并且TMV MP不会增加葡聚糖的这种尺寸排阻限制。相反，30-kD TMV MP本身在毛状体细胞之间移动，并特异性地介导90-kD β-葡萄糖醛酸酶（GUS）报告蛋白作为GUS：：TMV MP融合体的易位。无论是GUS本身还是在TMV MP存在下的GUS都不会在细胞间移动。这些数据意味着，胞间连丝运输信号驻留在TMV MP和运动是必不可少的。这种信号赋予选择性的易位蛋白质，不能反式发挥作用，以支持其他分子的运动。
Tobacco mosaic virus movement protein (TMV MP) is required to mediate viral spread between plant cells via plasmodesmata. Plasmodesmata are cytoplasmic bridges that connect individual plant cells and ordinarily limit molecular diffusion to small molecules and metabolites with a molecular mass up to 1 kD. Here, we characterize functional properties of Nicotiana clevelandii trichome plasmodesmata and analyze their interaction with TMV MP. Trichomes constitute a linear cellular system and provide a predictable pathway of movement. Their plasmodesmata are functionally distinct from plasmodesmata in other plant cel types; they allow cell-to-cell diffusion of dextrans with a molecular mass up to 7 kD, and TMV MP does not increase this size exclusion limit for dextrans. In contrast, the 30-kD TMV MP itself moves between trichome cells and specifically mediates the translocation of a 90-kD beta-glucuronidase (GUS) reporter protein as a GUS::TMV MP fusion. Neither GUS by itself nor GUS in the presence of TMV MP moves between cells. These data imply that a plasmodesmal transport signal resides within TMV MP and is essential for movement. This signal confers selectivity to the translocated protein and cannot function in trans to support movement of other molecules.