COLLABORATIVE: Functional Analysis of Arabidopsis Formins, a Family of Actin-Nucleating Proteins

合作：拟南芥福明（肌动蛋白成核蛋白家族）的功能分析

• 批准号: 0618334
• 负责人: Marcia Kieliszewski
• 金额: --
• 依托单位: Ohio University
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-10-01 至 2011-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0618334&HistoricalAwards=false
• 关键词: COLLABORATIVE; Functional; Analysis; Arabidopsis; Formins

Intellectual Merit: Actin microfilaments are critical cytoskeletal structures in all eukaryotes. The rate-limiting step in the formation of actin microfilaments is the polymerization of the first two to three monomeric actin protein molecules, known as actin nucleation. Formins are one of two known families of actin-nucleating proteins. Plant formins share similarity with their counterparts from other organisms in their actin-nucleating activity domain, but a large number of them (referred to as Group I plant formins) have the plant-unique feature of having a potentially glycosylated extracellular domain and a transmembrane domain that anchor the cytosolic actin-nucleating domain to the cell surface. This project aims to determine the functional roles of 3 group I formins from Arabidopsis, the pollen-specific AFH3, the pollen-, endosperm- and vegetative cell-expressed AFH5, and the root meristem-expressed AFH6, in plant growth and development. As group I formins, these AFHs serve as perfect candidates for mediating extracellular stimuli directly to the actin cytoskeleton, in a manner analogous to the function of integrins of animal cells. Drs. Cheung, Wu and Kieliszewski plan to elucidate the functional roles for these Group I AFHs in plant growth and development through a combination of genetic and cell biological analyses. The glycosylation properties of selected group I extracellular domains and the functional significance of the extracellular domains for these three AFHs (and that of AFH1, a prototypical and thus far the best-characterized plant formin) will be examined. Dr. Cheung and her colleagues will also begin efforts to identify proteins that interact with AFH3 and AFH5, which should lead to elucidation of the protein networks that underlie the regulation and functions of these plant formins. Broader Impacts: For resource development, Dr. Cheung and her colleagues will provide constructs, seeds and antibodies to the community. The PIs routinely host and train postdoctoral, graduate and undergraduate students in their laboratories, and plan to continue to do so in the context of this project. Since 1997, Dr. Cheung has mentored approximately 40 undergraduates, including several from unrepresented ethnic groups, and there are currently undergraduates participating in on-going efforts related to the project. Dr. Kieliszewski also consistently supervises undergraduates in her laboratory. Many of these undergraduates have gone on to graduate school in the sciences. Besides the PIs themselves, postdocs and senior graduate students in the Cheung and Kieliszewski laboratories all contribute to the direct training of undergraduates, therefore providing them with mentoring and teaching experience in preparation for their own future career development. Overall, this research project will provide a broad spectrum of training areas on different levels of sophistication suitable for students at the undergraduate, graduate and postdoctoral level.

智力优势：肌动蛋白微丝是所有真核生物的重要细胞骨架结构。肌动蛋白微丝形成的限速步骤是前两到三个单体肌动蛋白分子的聚合，称为肌动蛋白成核。形成蛋白是两个已知的肌动蛋白成核蛋白家族之一。植物形成蛋白在其肌动蛋白成核活性结构域中与来自其它生物体的对应物具有相似性，但它们中的大量（称为I类植物形成蛋白）具有植物特有的特征，即具有潜在糖基化的胞外结构域和跨膜结构域，所述跨膜结构域将胞质肌动蛋白成核结构域锚在细胞表面。本项目旨在研究拟南芥花粉特异性AFH3、花粉、胚乳和营养细胞表达的AFH5和根分生组织表达的AFH6这3种Ⅰ类formins在植物生长发育中的功能。作为I组formin，这些AFH作为完美的候选人直接介导细胞外刺激的肌动蛋白细胞骨架，在某种程度上类似于动物细胞的整合素的功能。Cheung、Wu和Kieliszewski博士计划通过遗传和细胞生物学分析的结合来阐明这些第I组AFH在植物生长和发育中的功能作用。将检查所选组I胞外结构域的糖基化特性和这三种AFH的胞外结构域的功能意义（以及AFH 1的功能意义，AFH 1是一种原型，迄今为止是最好的表征植物的胞外结构域）。Cheung博士和她的同事们还将开始努力鉴定与AFH3和AFH5相互作用的蛋白质，这将有助于阐明这些植物formins的调节和功能所依赖的蛋白质网络。更广泛的影响：在资源开发方面，张博士和她的同事将为社区提供构建体、种子和抗体。PI定期在其实验室接待和培训博士后，研究生和本科生，并计划在本项目的背景下继续这样做。自1997年以来，张博士指导了大约40名本科生，其中包括几名来自无代表族裔群体的本科生，目前有本科生参与与该项目有关的持续努力。Kieliszewski博士也一直在她的实验室监督本科生。这些本科生中有许多人继续攻读理科研究生。除了PI本身，张和Kieliszewski实验室的博士后和高年级研究生都有助于直接培训本科生，因此为他们提供指导和教学经验，为他们未来的职业发展做准备。总的来说，这个研究项目将提供一个广泛的培训领域在不同层次的复杂性，适合学生在本科生，研究生和博士后水平。