Dr. Gu received her PhD in Plant Genetics at University of California-Riverside (supervisor: Dr. Zhenbiao Yang). For her thesis work, she made important contributions at the molecular level to the understanding of polar growth (pollen tube) and diffuse growth (pavement cells). She worked as a postdoctoral fellow at Stanford University (supervisor: Dr. Chris Somerville) and as an associate specialist at University of California Berkeley when Dr. Somerville became the Director of Energy Biosciences Institute. Dr. Gu started her own lab at Penn State in 2010. Her group is part of the “Center for Lignocellulose Structure and Formation”, an Energy Frontier Research Center.
Department or University Committees
- Chair, Climate and Diversity Committee
- Promotion and Tenure Subcommittee
- Honors Advisors Committee
Program or Department Affiliations
|BMMB Graduate Program||Molecular, Cellular, and Integrative Biosciences||Plant Biology|
|2011 – present||Member, Editorial board, Frontiers in Plant Physiology|
|2011 – present||Member, Editorial board, Journal of Glycobiology|
|2017 – present||Academic Editor, Editorial board, Plant Direct|
|Center for Lignocellulose Structure and Formation||Center for Cellular Dynamics|
Molecular mechanisms of cellulose biosynthesis in plants
Gu Lab uses biochemical, molecular genetics, and spectroscopic approaches to decipher mechanisms of cellulose biosynthesis. Cellulose, often touted as the most abundant biopolymer on earth, is a major source of raw materials for paper, textiles, and an abundant source for sustainable and environment-friendly cellulosic biofuels. A long-term goal of our research is to gain a deeper understanding of the regulation of cellulose biosynthesis so that the fundamental knowledge can be transferred for designing new cellulosic materials with diverse economic applications.
1. Dissecting the mechanism by which microtubules guide cellulose deposition
Anisotropic growth is a hallmark of plant cell growth, which relies on mechanical anisotropic property of the cell wall, in particular, the ordered arrangement of cellulose microfibrils. Cortical microtubules are long known to influence the direction in which cellulose micorfibrils are deposited. However, the mechanism by which microtubules guide cellulose deposition is poorly understood. We use recently identified cellulose synthase interactive proteins to decipher the unknown mechanism. Our lab discovered that cellulose synthase interactive protein 1 (CSI1) links cellulose synthase complex (CSC) at the plasma membrane to the cortical microtubules. With this molecular link in our hand, we now begin to unravel the mystery of regulation of cellulose synthesis, which is critical to the growth morphogenesis of plant cells.
2. Endocytosis and recycling of cellulose synthase complex
Because cellulose synthesis occurs exclusively at the plasma membrane, the endocytosis and recycling of cellulose synthase (CESA) complex is an important mechanism for controlling the steady-state levels of CESA. We use cellulose synthase complex, a plant cell-specific cargo protein complex, to understand how endocytosis has evolved and are used by eukaryotic cells for diverse process. In particular, how TWD40-2 coordinate with AP2 adapter complex to regulate the endocytosis and recycling of cellulose synthase complex.
3. Secretion of cellulose synthase complex to the plasma membrane
The steady-state levels of CESA are influenced not only by endocytosis and recycling but also by exocytosis. Therefore secretion of cellulose synthase complexes to the plasma membrane becomes an important topic of our research. We use proteomics approaches, functional genetics and live cell imaging to decipher the mechanism of de novo secretion of cellulose synthase complexes. Our lab recently discovered that a plant-specific protein PATROL1 involved in secretion of cellulose synthase complex to the plasma membrane in coordination with exocyst complex. We aim to identify and characterize additional proteins that are important for delivery of CSCs to the plasma membrane.
Teaching and Mentoring
- Plant Biology Colloquium (PLBIO590), graduate course, FA18, SP19, FA19
- Plant Resource Acquisition and Utilization (PLBIO512), graduate lecture course, FA10, FA12
- Plant Communication and Growth Regulations (PLBIO513), graduate lecture course, SP10, SP15, SP16
- Modern Techniques and Concepts in Plant Cell Biology (PLBIO515), graduate lab course, FA12
- Freshmen Seminar (PSU016), undergraduate lecture course, SP11, FA12, FA13, FA14, FA18
- Eukaryotic Cell Biology (BMMB598D), graduate lecture course, SP12
- General Biochemistry (BMB401), large upper level undergraduate core biochemistry course, SP13, FA13, FA14, FA15, FA16
- General Biochemistry (BMB401H), undergraduate lecture course, FA18, FA19
Honors or Awards
- 2003 CEPCEB outstanding graduate student Award, UC Riverside
- 2002 Keystone Plant Signal Transduction Symposia Scholarship Award, Tahoe city, CA
- 2000 Graduate Student Award for the best oral presentation, UC Riverside
- 2000 Travel Mini Grant from Graduate Division, UC Riverside
- 1999-2000 Chancellor’s Distinguished Fellowship of UC Riverside
- Zhu X, Li S, Pan S, Xin X, Gu Y (2018) CSI1, PATROL1 and exocyst complex cooperate in delivery of cellulose synthase complexes to the plasma membrane. Proc. Natl. Acad. Sci. USA 115:E3578-3587.
- Li S, Bashline L, Zheng Y, Xin X, Huang S, Kong Z, Kim SH, Cosgrove D, Gu Y (2016) Cellulose synthase complexes act in a concerted fashion to synthesize highly aggregated cellulose in secondary cell walls of plants. Proc. Natl. Acad. Sci. USA 113(40): 11348-11353
- Lei L, Singh A, Bashline L, Li S, Yingling YG, Gu Y (2015) Cellulose synthase interactive 1 is required for a fast recycling of cellulose synthase complex to the plasma membrane in Arabidopsis. Plant Cell 27(10): 2926-2940
- Bashline L, Li S, Zhu X, Gu Y (2015) The TWD40-2 protein and the AP2 complex cooperate in the clathrin-mediated endocytosis of cellulose synthase to regulate cellulose biosynthesis. Proc. Natl. Acad. Sci. USA 112(41): 12870-12875
- Li S, Lei L, Yingling YG, Gu Y (2015) Microtubules and cellulose biosynthesis: the emergence of new players. Curr. Opin. Plant Biol. 28: 76-82
- Lei L, Zhang T, Strasser R, Lee CM, Gonneau M, Mach L, Vernhettes S, Kim SH, Cosgrove D, Li S, Gu Y (2014) The jiaoyao1 mutant is an allele of korrigan that abolishes endoglucanase activity and affects the organization of both cellulose microfibrils and microtubules in Arabidopsis. Plant Cell 26(6): 2601-2616
- Lei L, Li S, Juan Du, Bashline L, Gu Y (2013) Cellulose synthase interactive 3 regulates cellulose biosynthesis in both microtubule-dependent and microtubule-independent manner. Plant Cell 25(12): 4912-4923
- Li S, Lei L, Somerville C, Gu Y (2012) Cellulose synthase interactive protein 1 (CSI1) links microtubules and cellulose synthase complexes. Proc. Natl. Acad. Sci. 109 (1) 185-190.