Genetic and Structural Analyses of the TMV Movement Protein

9317368许多植物病毒引导一种或多种蛋白质的合成，这些蛋白质是感染从最初的部位向邻近细胞传播所必需的。就烟草花叶病毒而言，已确定并广泛研究了导致病毒传播的运动蛋白。然而，导致这种传播的细胞和分子机制还不是很清楚。以前的研究表明，运动蛋白促进病毒运动的能力是几种功能或特征结合的结果：1)与质膜结合；2)与细胞壁结合；3)与胞间连丝结合，是否在通道中形成纤维物质；4)修改胞间连丝的大小排除限制；5)形成大的、可溶的复合体，可能包括RNA。这项拟议的研究将确定生物活动所需的功能。运动蛋白的非功能突变体的互补将被用来确定可能负责不同功能的蛋白质区域。然后，将使用体外和体内研究相结合的方法来确定哪些功能与突变序列有关。病毒运动蛋白功能的研究结果将有助于更好地了解病毒感染是如何在植物中传播的。反过来，这可能会带来预防植物疾病的新方法。此外，由于运动蛋白与胞间连丝相互作用，所获得的知识将有助于更好地理解植物的细胞间通讯*

9317368 Beachy Many plant viruses direct the synthesis of one or more proteins required for the spread of infection from the initial; site to adjacent cells. In the case of tobacco mosaic virus the movement protein responsible for spread of the virus has been identified and extensively studied. Nevertheless, the cellular and molecular mechanism responsible for the spread are not well understood. Previous studies have suggested that the ability of the movement protein to facilitate virus movement is the result of a combination of several functions or characteristics: 1) association with plasma membranes; 2) association with cell walls; 3) association with plasmodesmata with or without the formation of fibrous material in the channel; 4) modification of the plasmodesmata size exclusion limit; 5) formation of large, soluble complex perhaps including RNA. The proposed research will determine which functions are required for biological activity. Complementation of nonfunctional mutants of the movement protein will be used to identify regions of the protein that may be responsible for separate functions. A combination of in vitro and in vivo studies will then be used to identify which functions are associated with the mutated sequences. %%% The results of the study on the function of the virus movement protein will lead to a better understanding of how viral infections spread in plants. In turn this may lead to novel methods in preventing plant diseases. In addition, because the movement protein interacts with plasmodesmata, the knowledge obtained will lead to a greater understanding of intercellular communication in plants ***