Collaborative Project: Cellular and Molecular Studies on Plasmodesmata

拟议的研究将整合生物物理，生物化学， 胞间连丝的细胞、生理和遗传学研究， 建立适当的框架， 研究植物调节的细胞过程 它的细胞间通讯系统 生物物理学研究将是 在简单的蜂窝系统上执行，以便确定酉 pd电导 这种测量对于进一步的子系统是必不可少的。 PD的结构分析，以及提供一个严格的 为详细研究细胞控制奠定了基础， 协调细胞到细胞的大小排除限制。 生理学研究 也将进行关于Pd在溶质通量中的作用的研究。 自从pd以来 可能是器官发育的重要决定因素， 将建立一个实验系统， 控制二次钯形成的过程。 这项正在进行 卢卡斯和华盛顿的罗杰·比奇博士的合作 圣路易斯大学），已经确定转基因烟草 表达TMV的30 kDa运动蛋白（MP）的植物 具有尺寸排阻限值上调至超过尺寸的PD 9.4 kDa。 30 kDa TMV-MP影响这种变化的方式 将进一步探讨。 假设这种蛋白质 直接与胞间连丝相互作用。 基于这一理念， 提出了PD蛋白的生物化学分离和纯化。 一 将开发拟南芥的遗传系统， 参与病毒移动和PD的基因的鉴定和分离 功能 胞间连丝是单个植物细胞之间的微观通道。 细胞间通讯通过分子通过这些 通道是至关重要的正常发展和生理 整个工厂的功能。 在某些植物病毒感染中， 病毒在局部位置进入细胞内部， 通过整个植物的胞间连丝从一个细胞传到另一个细胞。 病毒通过胞间连丝是由一种病毒性的 编码的蛋白质，有效地扩大胞间连丝通道。 这项研究将利用病毒蛋白来识别和 研究植物胞间连丝的组成。 知识 胞间连丝的成分将有助于进一步研究 胞间连丝的形成以及分子间连丝的形成机制 通过胞间连丝的运输受到调节。 的结果 研究将对细胞的基础知识做出重要贡献， 植物的细胞通讯

The proposed research will integrate biophysical, biochemical, cellular, physiological and genetic studies on plasmodesmata (pd) to establish an appropriate framework that will then allow an investigation of the cellular processes by which the plant regulates its cell-to-cell communication system. Biophysical studies will be performed on a simple cellular system in order to determine the unitary pd conductance. Such measurements are essential for a further sub- structural analysis of the pd, as well as to provide a rigorous foundation for detailed studies on the cellular controls that orchestrate cell-to-cell size exclusion limits. Physiological studies on the role of pd in solute fluxes will also be performed. Since pd are likely to be an important determinant of organ development, an experimental system will be established that will permit identification of the processes that control secondary pd formation. In this ongoing collaboration (between Lucas and Dr. Roger Beachy of Washington University, St. Louis), it has been established that transgenic tobacco plants in which the 30 kDa movement protein (MP) of TMV is expressed have pd whose size exclusion limits are up-regulated to sizes in excess of 9.4 kDa. The mode by which the 30 kDa TMV-MP effects this change will be further explored. It is hypothesized that this protein interacts directly with the plasmodesma. Based on this concept, biochemical isolation and purification of pd proteins are proposed. A genetic system in Arabidopsis will be developed to permit the identification and isolation of genes involved in virus movement and pd function. Plasmodesmata are microscopic channels between individual plant cells. Intercellular communication by passage of molecules through these channels is critical for the normal development and physiological function of the entire plant. In certain plant viral infections, the virus gains access to the cell interior at a localized site and passes from cell to cell through the plasmodesmata throughout the plant. Passage of the virus through plasmodesmata is facilitated by a virally encoded protein which effectively enlarges the plasmodesmatal channel. This research will take advantage of the viral protein to identify and study the components of the plant plasmodesmata. Knowledge of the components of plasmodesmata will facilitate further studies of the formation of plasmodesmata and the mechanisms by which molecular traffic through the plasmodesmata is regulated. The results of this research will be important contributions to basic knowledge of cell to cell communication in plants.