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

了解植物细胞如何制造纤维素不仅将为利用遗传工具诱导植物制造修饰细胞壁提供科学基础，从而在可持续能源方面取得重大进展，而且还将为植物细胞如何决定细胞扩增和细胞最终形状的重要基础科学问题提供有价值的见解。该项目还将为本科生，特别是妇女和代表性不足的少数民族提供研究机会。个别研究项目将根据不同的本科研究项目进行调整，以吸引有才能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。该项目还将包括在宾夕法尼亚州立大学以实践研究研讨会的形式参加一个面向当地高中女生及其教师的推广活动。纤维素微原纤维是由一种叫做纤维素合酶复合物（CSC）的大蛋白质复合物在质膜上合成的。CSC吸收糖单体并组装成线性聚合物，结晶纤维素微原纤维，这是地球上最丰富的生物聚合物。由于纤维素的合成发生在质膜上，因此了解纤维素合酶运输到细胞表面的机制变得非常重要。活细胞成像、功能遗传学和蛋白质组学方法的强大组合将用于研究植物细胞如何利用胞外作用将CSC传递到细胞表面。具体而言，将解决以下三个目标：1)确定植物特异性蛋白PATROL1和保守的胞囊复合物在纤维素生物合成中的作用。2)确定CSCs与PATROL1和胞囊复合物的关系。3)通过对其合作伙伴的功能表征，明确PATROL1在CSC分泌中的作用。总之，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。该项目将成为训练本科生、高中生和教师，特别是妇女和代表性不足的少数民族在实验性科学研究方面的工具。该奖项反映了美国国家科学基金会的法定使命，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.