A Molecular Link Between Actin and Exocytosis

智力优势：单个细胞的极化生长是一个综合细胞代谢事件和细胞外环境的复杂过程。延伸和形状的变化经常伴随着物质沉积到它们的细胞外环境。在植物中，细胞也构建了一个碳水化合物聚合物网络，作为一个刚性屏障，被称为细胞壁。植物细胞通过构建新的细胞壁材料来生长，植物细胞的形状与这些材料如何沉积在细胞外部密切相关。该项目将致力于阐明细胞壁材料的输送与细胞内部动态细丝网络（称为细胞骨架）之间的联系。特别是，PI将使用复杂的光学显微镜成像方法来测试双胍蛋白对靶向肌动蛋白组装过程至关重要的假设，该过程启动细胞壁物质胞外作用。虽然已知细胞生长和细胞骨架密切相关，但对这种耦合的详细机制理解仍有待阐明。这个项目将利用苔藓，一个简单的，遗传上可处理的植物模型系统，来解决这个基本的细胞生物学问题。更广泛的影响：研究者将通过向植物研究界提供资源和专业知识，培训本科生和未被充分代表的少数民族，并将项目的各个方面纳入本科教育，来扩大拟议研究的影响。苔藓模型系统非常适合本科生的实验室经验。因此，研究者还将开发一个基于项目的实验课程，其中学生进行rna诱导沉默实验，以分析单个基因的功能及其在细胞生长中的作用。此外，马萨诸塞大学STEM多样性研究所（STEM Diversity Institute）提供的一个夏季实验室模块将旨在增加未被充分代表的少数族裔的参与和招募。夏季模块的课程材料将分发给合作院校中代表性不足的教员，以促进类似课程的实施。将教师和学生纳入这一努力将有助于增加科学的多样性。

Intellectual Merit: Polarized growth of individual cells is a complex process integrating cellular metabolism events and the extracellular environment. Extension and shape changes are frequently accompanied with deposition of material into their extracellular environments. In plants, cells also build a network of carbohydrate polymers that act as a rigid barrier, known as the cell wall. Plant cells grow by building new cell wall material and plant cell shape is intimately linked with how this material is deposited on the outside of the cell. This project will work to elucidate the link between delivery of cell wall material and the cell's internal network of dynamic filaments known as the cytoskeleton. In particular the PI will use sophisticated light microscope imaging methods to test the hypothesis that formin proteins are critical for targeting actin assembly processes that initiate cell wall material exocytosis. Although it is known that cell growth and the cytoskeleton are intimately connected, a detailed mechanistic understanding of this coupling remains to be elucidated. This project will take advantage of moss, a simple, genetically tractable plant model system, to address this fundamental cell biological question.Broader Impacts: The investigator will broaden the impacts of the proposed research by providing resources and expertise to the plant research community, training of undergraduates and underrepresented minorities, and incorporating aspects of the project in undergraduate education. The moss model system is ideally suited for undergraduate laboratory experiences. Therefore, the investigator will also develop a project-based laboratory course wherein students perform RNA-induced silencing experiments to analyze the function of individual genes and their roles in cell growth. Additionally, a summer laboratory module offered through the STEM Diversity Institute at U. Mass will aim to increase participation and recruitment of underrepresented minorities. Course materials from the summer module will be distributed to underrepresented faculty at partner institutions to facilitate implementation of similar courses. Incorporating faculty and students in this endeavor will contribute to increasing diversity in the sciences.