Molecular analysis of SCD complex function in Rab signaling in cell morphogenesis and function

该项目的目标是更好地了解植物细胞如何分裂和扩大，这是植物生长和健康所必需的植物生物学的关键方面。细胞分裂的最后一步，称为胞质分裂，涉及细胞分裂成两个子细胞，然后是新细胞的扩增。 然而，这些过程中涉及的许多机制在植物或动物中都没有得到很好的理解。具体而言，该项目将重点关注新的膜屏障和细胞壁如何在新分裂的植物细胞之间和周围形成。所获得的信息有可能揭示提高美国农场作物产量和质量的新策略，以提高粮食安全和能源独立性。此外，高中，本科，研究生和研究生水平的年轻科学家将接受生物化学，遗传学和显微镜领域的高级研究培训。研究生和博士后研究员也将通过监督高中和本科生，包括在威斯康星大学麦迪逊分校IBS夏季研究计划中代表性不足的学生，获得教学和指导技能。此外，该项目还将为工厂和一般研究社区提供研究工具，包括用于定量跟踪生物分子和非生物材料的图像分析软件。本研究的长期目标是了解植物生长发育所需的细胞质膜运输的分子机制，包括：胞质分裂、细胞壁生物合成、激素信号、营养吸收和病原体防御。SCD 1和SCD 2编码细胞质分裂、细胞扩增和病原体防御所必需的植物特异性网格蛋白包被的囊泡蛋白。最近的研究表明，SCD 1和SCD 2是一个以前未表征的蛋白质复合物的亚基，与Rab蛋白相互作用，这是囊泡运输的中央调节器。本项目的重点是研究这种新发现的SCD复合物的功能及其在分裂和非分裂细胞中对Rab/网格蛋白依赖性膜运输的调节。本项目的具体目标是：1）生物化学表征SCD复合物的组成和活性，2）定义SCD/Rab复合物的效应子和调节子，3）开发和应用定量成像方法来分析和描述SCD复合物及其同源Rab在植物细胞形态建成所必需的细胞内膜运输中的功能。这些研究将产生植物特异性和进化上保守的膜运输蛋白在植物和其他真核系统中的功能的基础知识。

The objectives of this project are to better understand how plant cells divide and enlarge, which are key aspects of plant biology necessary for the growth and health of plants. The final step of cell division, known as cytokinesis, involves the splitting of a cell into two daughter cells and is followed by expansion of the new cells. However, many of the mechanisms involved in these processes are not well understood in either plants or animals. Specifically, this project will focus on how new membrane barriers and cell wall form between and around newly divided plant cells. The information gained has the potential to reveal new strategies for improving crop yield and quality on American farms necessary for increased food security and energy independence. In addition, young scientists at the high school, undergraduate, graduate, and postgraduate level will receive advanced research training in the areas of biochemistry, genetics and microscopy. Graduate students and postdoctoral fellows will also gain teaching and mentoring skills by supervising high school and undergraduates including underrepresented students in the UW-Madison IBS Summer Research Program. Additionally, the project will generate research tools for both the plant and the general research communities including image analysis software for the quantitative tracking of biological molecules and non-biological materials. The long-term objective of this project is to understand the molecular mechanisms involved in intracellular membrane trafficking required for plant growth and development including: cytokinesis, cell wall biosynthesis, hormone signaling, nutrient uptake, and pathogen defense. SCD1 and SCD2 encode plant-specific clathrin-coated vesicle proteins necessary for cytokinesis, cell expansion and pathogen defense. Recent studies have demonstrated that SCD1 and SCD2 are subunits of a previously uncharacterized protein complex that interacts with Rab proteins, which are central regulators of vesicle trafficking. The focus of this project is to investigate the function of this newly identified SCD complex and its regulation of Rab/clathrin-dependent membrane trafficking in dividing and non-dividing cells. The specific aims of this project are to 1) Biochemically characterize the composition and activity of the SCD complex, 2) Define effectors and regulators of the SCD/Rab complex, and 3) Develop and apply quantitative imaging approaches to analyze and describe the function of the SCD complex and its cognate Rabs in intracellular membrane trafficking necessary for plant cell morphogenesis. These studies will generate fundamental knowledge into the function of plant-specific and evolutionarily conserved membrane-trafficking proteins in plants and other eukaryotic systems.