Structure and Assembly of Helical Plant Viruses

一些螺旋植物病毒的结构将被 以足以描述完整的 病毒的分子细节，使用纤维衍射方法 已经在这个实验室成功地用于烟草花叶病 病毒（TMV）和TMV的U2株系。 要研究的病毒 包括与TMV（黄瓜绿色斑驳病）远缘病毒 花叶病毒和牛筋草花叶病毒），以及不相关的 番木瓜花叶病毒（PMV）。 的结构 将测定PMV的分离外壳蛋白 晶体学上。 TMV的突变体，预测从 结构在组装或拆卸方面存在缺陷， 在这里设计并由合作者制作。 他们的集会和 在这里，将研究电子的分解性质。 显微镜和其他测量。 突变体的结构显示 将确定显著改变的组件特性。 %%% 这些杆状病毒是唯一一种 可以使用X射线衍射方法观察核酸基因组。 研究它们的结构对于理解 蛋白质-核酸相互作用和分子过程 在生物系统中的组装和识别。 组件和 识别是许多细胞过程中的重要步骤， 以及在病毒感染和繁殖过程中。 的 因此，这里提出的研究与各种各样的 对医学和农业都很重要的细胞系统。

The structures of a number of helical plant viruses will be determined at resolutions sufficient to describe the intact viruses in molecular detail, using the fiber diffraction methods already used successfully in this laboratory for tobacco mosaic virus (TMV) and the U2 strain of TMV. The viruses to be studied include viruses distantly related to TMV (cucumber green mottle mosaic virus and ribgrass mosaic virus), and the unrelated potexvirus papaya mosaic virus (PMV). The structure of the isolated coat protein of PMV will be determined crystallographically. Mutants of TMV, predicted from the structure to be deficient in assembly or disassembly, will be designed here and made by collaborators. Their assembly and disassembly properties will be studied here by electron microscopy and other measurements. Structures of mutants showing significantly changed assembly properties will be determined. %%% These rod-shaped viruses are the only viruses in which the entire nucleic acid genome can be seen using x-ray diffraction methods. Studies of their structures are important to understanding protein-nucleic acid interactions and the processes of molecular assembly and recognition in biological systems. Assembly and recognition are essential steps in many cellular processes, as well as in the processes of viral infection and propagation. The studies proposed here are therefore relevant to a wide variety of cellular systems of both medical and agricultural importance.