Proteomic approaches and live cell imaging reveal unique aspects of delivery of cellulose synthase complexes to the plasma membrane

了解植物细胞是如何制造纤维素的，不仅将为利用遗传工具诱使植物制造修饰细胞壁以实现可持续能源的重大进步提供科学基础，而且还将为植物细胞如何决定细胞扩张和最终细胞形状等重要和基本的科学问题提供宝贵的见解。该项目还将为本科生，特别是女性和代表性不足的少数群体提供研究机会。个人研究项目将根据不同的本科生研究项目进行量身定做，以吸引有才华的女性和代表性不足的学生，并加强他们为研究生院和学术生涯做准备。该项目还将包括参加在宾夕法尼亚州立大学举办的以实践研究讲习班的形式向当地高中女生及其教师举办的外联活动。纤维素微纤维是由一种叫做纤维素合成酶复合体(CSC)的大型蛋白质复合体在质膜上合成的。CSC吸收了糖单体，并组装了一种线性聚合物，结晶纤维素微纤维，这是地球上含量最丰富的生物聚合物。由于纤维素的合成发生在细胞膜上，因此了解纤维素合成酶运输到细胞表面的机制变得非常重要。我们将结合活细胞成像、功能遗传学和蛋白质组学方法来研究植物细胞如何利用胞吐作用将CSC运送到细胞表面。具体地说，将解决以下三个目标：1)确定植物特有蛋白PATROL1和保守的胞外囊体复合体在纤维素生物合成中的作用。2)确定CSCs如何与PATROL1和胞囊复合体相关联。3)确定PATROL1在CSC分泌中的作用，通过对其伙伴的功能鉴定。总而言之，这些实验将为真核细胞运输机制的进化提供前所未有的见解。该项目将是在实验科学调查的背景下培训本科生、高中生和教师，特别是女性和代表性不足的少数民族的工具。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

An understanding of how plant cells make cellulose will not only provide scientific foundations for using genetic tools to coax plants into making modified cell walls for significant advances in sustainable energy, but also provide valuable insights for important and basic scientific questions of how a plant cell determines cell expansion and the final shape of the cell. This project will also provide research opportunities to undergraduate students, especially women and underrepresented minorities. Individual research projects will be tailored to various undergraduate research programs to attract talented women and underrepresented students and to enhance their preparation for graduate school and academic careers. This project will also include participation in an outreach event to local high school girls and their teachers in the form of a hands-on research workshop at Pennsylvania State University. Cellulose microfibrils are synthesized at the plasma membrane by a large protein complex called cellulose synthase complex (CSC). The CSC uptakes sugar monomers and assembles a linear polymer, crystalline cellulose microfibrils, which are the most abundant biopolymer on earth. Because cellulose synthesis occurs at the plasma membrane, understanding the mechanisms by which cellulose synthase is trafficked to the cell surface becomes very important. A robust combination of live cell imaging, functional genetics, and proteomics approaches will be used to study how plant cells use exocytosis to deliver CSC to the cell surface. Specifically, the following three objectives will be addressed: 1) Determine the role of plant-specific protein PATROL1 and the conserved exocyst complex in cellulose biosynthesis. 2) Determine how CSCs are associated with PATROL1 and the exocyst complex. 3) Define the role of PATROL1 in CSC secretion through functional characterization of its partners. Together, these experiments will provide unprecedented insights into the evolution of trafficking machinery of eukaryotic cells. The project will be a vehicle for training undergraduate students, high school students and teachers, especially women and underrepresented minorities, in the context of experimental scientific enquiry.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.