The Exocyst and Vesicle Trafficking In Plant Development

PI: John E. FowlerNSF提案# IOS-0920747：“植物发育中的囊泡和囊泡运输”在每个植物细胞内，微小的膜结合囊泡将植物生长和发育所必需的各种物质携带到质膜，这有助于形成细胞。年代边界。这些囊泡在正确的时间被准确地传递到质膜上正确的位置的机制尚不清楚，尽管这种严格的调节是细胞分裂、细胞壁延伸、防御病原体和细胞间通讯（例如植物激素信号）等过程的基础。该项目将研究一种由八种蛋白质组成的特殊复合物，即囊泡在这种囊泡运输中的作用。根据对酵母和哺乳动物系统的研究，外囊被假设为囊泡与其在质膜上的预定位置之间的系带，有助于在发育适当的时间将囊泡定位到特定的位置。胞囊蛋白的突变证明了胞囊在植物中的重要性，这种突变会导致花粉管生长缺陷、茎伸长减少和矮化（包括短根）。本项目将利用遗传学、生物化学和细胞生物学的方法来更具体地研究胞囊？在囊泡运输、植物激素信号传导和细胞分裂中可能发挥的作用，并将研究模式植物拟南芥的花粉管伸长和初生根生长。这项工作可能会产生更广泛的影响，为寻求改变植物生长、细胞壁（例如生物燃料）或农作物病原体反应的应用工作提供信息。该项目将培养一名博士后研究员和一名研究生，促进与捷克共和国研究人员的富有成效的合作，并为当地的小学生和中学生提供科学宣传。

PI: John E. FowlerNSF Proposal # IOS-0920747: "The Exocyst and Vesicle Trafficking In Plant Development"Inside each plant cell, tiny membrane-bound vesicles carry a variety of materials essential for plant growth and development to the plasma membrane, which helps form the cell?s boundary. The mechanism by which these vesicles are delivered to the correct location on the plasma membrane at precisely the right time is not well understood, even though this tight regulation is fundamental to such processes as cell division, cell wall elongation, defense against pathogens, and intercellular communication (e.g., plant hormone signaling). This project will study the role of a particular complex of eight proteins, the exocyst, in such vesicle trafficking. Based upon work in yeast and mammalian systems, the exocyst is hypothesized to work as a tether between a vesicle and its intended location at the plasma membrane, helping to target vesicles to specific sites at developmentally appropriate times. The importance of the exocyst in plants is demonstrated by mutations in exocyst proteins, which cause defective pollen tube growth, reduced stem elongation in the dark, and dwarfism (including short roots). This project will utilize genetic, biochemical, and cell biological methods to more specifically investigate the exocyst?s possible roles in vesicle trafficking, phytohormone signaling, and cytokinesis (cell division), and will examine both pollen tube elongation and primary root growth in the model plant, Arabidopsis thaliana. This work is likely to have broader impacts by informing applied work that seeks to modify plant growth, cell walls (e.g., for biofuels), or pathogen response in agricultural crops. This project will train a postdoctoral researcher and a graduate student, foster a productive collaboration with researchers in the Czech Republic, and provide science outreach to local elementary and high school students.