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

这个项目的目标是更好地了解植物细胞是如何分裂和扩大的，这是植物生物学中对植物生长和健康所必需的关键方面。细胞分裂的最后一步，称为胞质分裂，包括将一个细胞分裂成两个子细胞，然后是新细胞的扩张。然而，这些过程中涉及的许多机制在植物和动物中都不是很好的理解。具体地说，这个项目将集中在新分裂的植物细胞之间和周围如何形成新的膜屏障和细胞壁。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战略，这是加强粮食安全和能源独立所必需的。此外，高中、本科、研究生和研究生水平的青年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还将通过指导高中和本科生，包括威斯康星大学麦迪逊分校IBS暑期研究项目中的未充分代表的学生，获得教学和指导技能。此外，该项目将为植物和一般研究社区生成研究工具，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。该项目的长期目标是了解植物生长发育所需的细胞膜运输的分子机制，包括：细胞质分裂、细胞壁生物合成、激素信号转导、营养吸收和病原菌防御。SCD1和SCD2编码植物特有的囊泡蛋白，是胞质分裂、细胞扩张和病原体防御所必需的。最近的研究表明，SCD1和SCD2是以前未知的蛋白复合体的亚基，它与Rab蛋白相互作用，Rab蛋白是囊泡运输的中央调节因子。本项目的重点是研究这个新发现的SCD复合体的功能及其对分裂和非分裂细胞中依赖于Rab/clathrin的膜转运的调节。本项目的具体目标是：1)对SCD复合体的组成和活性进行生化表征；2)确定SCD/Rab复合体的效应子和调节子；3)开发和应用定量成像方法来分析和描述SCD复合体及其同源RAB在植物细胞形态发生所必需的细胞膜运输中的功能。这些研究将产生植物特有的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.