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: 2154573
• 负责人: Luis Vidali
• 金额: $ 45万
• 依托单位: Worcester Polytechnic Institute
• 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=2154573&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，其调节细胞内部与其环境之间的物质的进出。 在植物中，质膜被细胞壁包围，提供额外的机械强度和保护。植物细胞的分裂和扩展需要大量的新质膜和细胞壁物质的产生。此外，位于质膜上的蛋白质的活性、分布和丰度的调节对于植物生长和健康所必需的许多细胞过程是非常关键的，包括营养吸收、激素信号传导、病原体感知、应激反应和细胞壁的构建。 这个项目将侧重于了解质膜形成和维持所需的材料的输送是如何在分裂和扩大细胞控制。更广泛的影响活动包括研究的内在价值，因为预计这些研究中获得的信息将导致开发新的工具和战略，通过改进生物燃料和其他重要农业产品的生产，提高粮食安全和能源独立所需的作物产量和质量。除了经济和科学效益外，该项目还将为本科生和研究生一级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生物化学、遗传学和显微镜等现代细胞生物学研究基础领域的高级培训。在植物中，多亚基SCD复合体通过胞吐作用将膜、蛋白质和细胞壁物质输送到质膜上。SCD复合物的主要亚基包括含DENN结构域的蛋白质，SCD 1（气孔胞质分裂缺陷1）和卷曲螺旋蛋白质，SCD 2，先前已被证明是必需的细胞质分裂和细胞生长所需的拟南芥膜运输。此外，生化研究已经确定了SCD复合物的另一个亚基，MyTH 1，它与后生动物I类肌球蛋白的膜结合结构域有关。SCD复合体亚基的同源物存在于陆地植物和绿色藻类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复合体是古老的进化起源。该项目的具体目标是：1）定义SCD复合物的生化活性和调节，2）描绘蛋白质-蛋白质和蛋白质-脂质相互作用的网络，这些网络控制SCD复合物组装和胞外膜运输所需的膜缔合，3）在模式系统拟南芥和立碗藓中进行SCD 1，SCD 2和MyTH 1同源物的比较研究。这些相结合的方法将提供深入了解关键的保守和不同的功能SCD复杂的亚基，必要的外泌贩运，延伸跨越被子植物和brabrites之间的进化距离。此外，由于胞吐作用的机制迄今为止主要在缺乏SCD复合物的酵母和后生动物模型系统中进行了研究，因此该项目将产生其他植物和真核生物的胞吐分子机制的基础知识，这对海洋，淡水，该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查进行评估，被认为值得支持的搜索.