Collaborative Research: Regulation of exocytic membrane trafficking required for cytokinesis and polarized cell expansion

合作研究：胞质分裂和极化细胞扩张所需的胞吐膜运输的调节

• 批准号: 2154572
• 负责人: Sebastian Bednarek
• 金额: $ 85万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-06-15 至 2026-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2154572&HistoricalAwards=false
• 关键词: Collaborative; Research; Regulation; exocytic; membrane

The plasma membrane is the outer membrane of all cells that regulates the entry and exit of material between the inside of the cell and its environment. In plants, the plasma membrane is surrounded by a cell wall that provides additional mechanical strength and protection. Production of large amounts of new plasma membrane and cell wall material is essential for plant cell division and expansion. In addition, regulation of the activity, distribution, and abundance of proteins located at the plasma membrane is highly critical for numerous cellular processes essential for growth and health of plants, including nutrient uptake, hormone signaling, pathogen perception, stress responses, and construction of the cell wall. This project will focus on understanding how the delivery of material required for plasma membrane formation and maintenance is controlled in dividing and expanding cells. Broader Impact activities include the intrinsic merit of the research as it is expected that the information gained in these studies will lead to the development of new tools and strategies for enhancing yield and quality of crop plants necessary for food security and energy independence through the improved production of biofuels and other agronomically important products. In addition to its economic and scientific benefits, this project will also provide important research training for young scientists at the undergraduate and graduate level. Students involved in this project will receive advanced training in the areas of biochemistry, genetics, and microscopy fundamental to modern cell biology research.In plants, the multisubunit SCD complex is essential for the delivery of membrane, proteins, and cell wall material to the plasma membrane by a process known as exocytosis. Major subunits of the SCD complex include the DENN domain-containing protein, SCD1 (stomatal cytokinesis defective1) and the coiled-coil protein, SCD2, which have previously been shown to be necessary for membrane trafficking required for cytokinesis and cell growth in Arabidopsis thaliana. Additionally, biochemical studies have identified another subunit of the SCD complex, MyTH1, which is related to the membrane-binding domain of metazoan class I myosins. Homologs of SCD complex subunits are present in land plants and green algae as well as other eukaryotes but were lost in yeast and metazoans, suggesting that the SCD complex is of ancient evolutionary origin. The specific aims of this project are to 1) define the biochemical activity and regulation of the SCD complex, 2) delineate the network of protein-protein and protein-lipid interactions that govern SCD complex assembly and membrane association required for exocytic membrane trafficking and 3) perform comparative studies of SCD1, SCD2, and MyTH1 homologs in the model systems Arabidopsis and Physcomitrium (Physcomitrella) patens. These combined approaches will provide insights into critical conserved and divergent functions of SCD complex subunits, necessary for exocytic trafficking, extending across the evolutionary distance between angiosperms and bryophytes. In addition, as the mechanisms of exocytosis have to date been primarily studied in yeast and metazoan model systems lacking the SCD complex, this project will generate fundamental knowledge of the exocytic molecular machinery of other plants and eukaryotes, which are important for the diversity and health of marine, freshwater, and terrestrial ecosystems.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

质膜是所有细胞的外膜，可调节细胞内部及其环境之间的物质进入和退出。 在植物中，质膜被细胞壁包围，可提供额外的机械强度和保护。生产大量新的质膜和细胞壁材料对于植物细胞分裂和膨胀至关重要。此外，位于质膜上的蛋白质的活性，分布和丰度的调节对于众多对植物生长和健康所必需的细胞过程至关重要，包括营养摄取，激素信号传导，病原体感知，应激反应，压力反应和细胞壁的结构。 该项目将集中于理解质膜形成和维护所需的材料如何在分裂和扩展细胞中控制。更广泛的影响活动包括研究的内在优点，因为预计这些研究中获得的信息将导致开发新工具和策略，以通过改善生物燃料和其他农艺重要产品的生产来增强粮食安全和能源独立性所必需的作物植物的产量和质量。除了经济和科学利益外，该项目还将为本科和研究生层面的年轻科学家提供重要的研究培训。参与该项目的学生将接受对现代细胞生物学研究基础的生物化学，遗传学和显微镜的高级培训。 SCD复合物的主要亚基包括含DENN结构域的蛋白质，SCD1（气孔细胞因子有缺陷1）和盘绕蛋白SCD2，这些蛋白SCD2先前被证明是拟南芥中细胞因子和细胞生长所需的膜运输所必需的。此外，生化研究还确定了SCD复合物神经1的另一个亚基，这与后生一类I类肌球蛋白的膜结合结构域有关。 SCD复杂亚基的同源物存在于陆地植物和绿藻以及其他真核生物中，但在酵母和后生动物中丢失，这表明SCD综合体是古代进化起源。该项目的具体目的是1）定义SCD复合物的生化活性和调节，2）描绘蛋白质 - 蛋白质 - 蛋白质和蛋白质 - 脂质相互作用网络，该网络控制了SCD复合体组装和膜膜运输所需的SCD复合体和膜关联，并进行SCD1，SCD1，SCD2和我的Myth1 Qualods的比较研究。 （Physcomitrella）Patens。这些合并的方法将提供有关SCD复合体亚基的关键保守和不同功能的见解，这对于外胞送运输所需，并在被子植物和苔藓植物之间的整个进化距离上延伸。此外，由于迄今为止必须在缺乏SCD综合体的酵母和后代模型系统中研究胞吞作用的机制，因此该项目将产生对其他植物和真核生物的卵细胞分子机械的基本知识，这些杂物细胞机械对于海洋，淡水，近代和地面的养生量很重要，这对于宣布的纽约市的多样性和健康状况都在现场宣布。通过基金会的智力优点和更广泛的影响评估标准通过评估来支持。