Guangpu Li, PhD


Contact Information:

Office:  BRC 417B

Phone: (405) 271-2227  ext. 61232
Fax:(405) 271-3092

Mailing Address:
975 NE 10th Street. BRC419
Oklahoma City, OK  73104


PhD, Washington University, St. Louis, 1991

Research Interests:

Endocytosis/endosome fusion: molecular mechanism and function in signal transduction and regulation of cell growth and differentiation

Cells are basic building blocks of living organisms. Endocytosis is a fundamental cellular process for uptake of nutrients, regulation of cell surface receptors, and maintenance of cell homeostasis. While it is an important cellular function, endocytosis is often employed by microorganisms like viruses for entry and infection of cells.

Our research is directed towards understanding the molecular basis of endocytosis and its role in regulation of cell growth and differentiation, which may provide valuable knowledge on how this cellular process is involved in human diseases such as cancer and infectious diseases and whether endocytosis can be targeted to develop therapeutics. 

Current projects include (1) mechanism of Rab5-regulated endosome fusion, which is a critical step during  endocytosis and (2) Role of endocytosis in nerve growth factor (NGF)-mediated signal transduction and neuron differentiation. We hope to describe endocytosis/endosome fusion in molecular terms and identify regulatory mechanisms that control the activity of these cellular processes during cell growth and differentiation.

Selected Publications:

  • Li G and Marlin MC (2015). Rab family of GTPases. In: Rab GTPases: Methods in Molecular Biology, G. Li ed., Springer.

  • Marlin MC and Li G (2015). Differential effects of overexpression of Rab5 and Rab22 on autophagy in PC12 cells with or without NGF. In: Rab GTPases: Methods in Molecular Biology, G. Li, ed., Springer.

  • Qi Y, Liang Z, Wang Z, Lu G, and Li G  (2015). Determination of Rab5 activity in the cell by effector pull-down assay. In: Rab GTPases: Methods in Molecular Biology, G. Li, ed., Springer.

  • Marlin MC and Li G (2015). Biogenesis and function of the NGF/TrkA signaling endosomes. Int Rev Cell Mol Biol, 314, 239-257. PMCID: PMC4307610

  • Maskey D, Marlin MC, Kim S, Kim S, Ong EC, Li G, and Tsiokas L  (2015). Cell cycle-dependent ubiquitylation and destruction of NDE1 by CDK5-FBW7 regulates ciliary length. EMBO J, In press.

  • Zheng H, Zheng W, Wu C, Yang J, Xi Y, Xie Q, Zhao X, Deng X, Lu G, Li G, Ebbole D, Zhou J, and Wang Z (2015). Rab GTPases are essential for membreane-trafficking-dependent growth and pathogenicity in Fusarium graminearum. Environ Microbiol, In press.

  • Qi Y, Marlin MC, Liang Z, Berry W, Janknecht R, Zhou J, Wang Z, Lu G, and Li G (2014). Distinct biochemical and functional properties of two Rab5 homologs from the rice blast fungus Magnoporthe oryzae. J Biol Chem, 289, 28299-28309.  PMCID: PMC4192484

  • Okon IS, Coughlan KA, Zhang C, Moriasi C, Ding Y, Song P, Zhang W, Li G, and Zou M-H (2014). Protein kinase LKB1 promotes Rab7-mediated neurophilin-1 degradation to inhibit angiogenesis. J. Clin. Invest. 124, 4590-4602PMCID: PMC4191012

  • D’Souza-Schorey C and Li G (2013). Endocytosis and the Regulation of Cell Signaling, Cell Adhesion, and Epithelial to Mesenchymal Transition in Cancer. In: Vesicle Trafficking in Cancer, Y. Yarden & G. Tarcic, ed., Springer.

  • Dou Z, Pan J-A, Dbouk HA, Ballou LM, DeLeon JL, Fan Y, Chen J-S, Liang Z, Li G, Backer JM, Lin RZ, and Zong W-X (2013). Class IA PI3K p100b subunit promotes autophagy through Rab5 small GTPase in response to growth factor limitation. Mol Cell, 50:1-14. 

  •  Li G (2012). Early Endocytosis: Rab5, Rab21 and Rab22. In: Rab GTPases and Membrane Trafficking, G. Li & N. Segev, ed., Bentham Science Publishers Ltd.
  • Wang L, Liang Z, and Li G (2011) Rab22 controls NGF signaling and neurite outgrowth in PC12 cells.  Mol Biol Cell 22(20):3853-60.
  • Li G (2011) Rab GTPases, membrane trafficking and diseases. Curr Drug Targets,12:1188-93
  • Zhu H, Qian H, and Li G (2010), Delayed onset of positive feedback activation of Rab5 by Rabex-5 and Rabaptin-5 in endocytosis. PLoS ONE, 5(2):e9226.
  • Zhu, H, Liang Z, Li, G. (2009) Rabex-5 is a Rab22 effector and mediates a Rab22-Rab5 signaling cascade in endocytosis.  Mol Biol Cell 20(22):4720-9.
  • Zhu, H., Zhu, G., Liu, J., Liang, Z., Zhang, X.C., and Li, G. (2007) Rabaptin-5-independent Membrane Targeting and Rab5 Activation by Rabex-5 Mol. Biol. Cell 18:4119-4128.
  • Zhu, G., Chen, J., Liu, J., Brunzelle, J.S., Huang, B., Wakeham, N., Terzyan, S., Li, X., Rao, Z., Li, G., and Zhang, X.C. (2007) Structure of the APPL1 BAR-PH domain and  characterization of its interaction with Rab5. EMBO J. 26:3484-3493.

  • Liu, J., Lamb, D., Chou, M., Liu, Y-J., Li, G. (2007) Nerve Growth Factor-mediated Neurite Outgrowth via Regulation of Rab5. Mol. Bio. Cell 18:1375-1384.

  • Liang, Z. and Li, G. (2005) Recombinant Sindbis virus expressing functional GFP in the nonstructural protein nsP3. Gene Therapy & Mol. Bio. 9:317-324.

  • Zhu, G., Zhai, P., Liu, J., Terzyan, S., Li, G., and Zhang, X. C. (2004) Structural basis of Rab5-Rabaptin5 interaction in endocytosis. Nature Struc. & Mol. Biol. 11:975-983.

  • Zhu, G., Zhai, P., He, X., Wakeham, N., Rodgers, K., Li, G., Tang, J., and Zhang, X. C. (2004) Crystal structure of human GGA1 GAT domain complexed with the GAT-binding domain of Rabaptin5. EMBO J. 23:3909-3917.

  • Li, G. and Zhang, X.C. (2004) GTP hydrolysis mechanism of Ras-like GTPases. J. Mol. Biol. 340:921-932.

  • Liang, Z., Veeraprame, H., Bayan, N., and Li, G. (2004) C-terminus of prenylin is important in forming a dimer conformation necessary for ER to Golgi transport. Biochem. J. 380:43-49

  • Terzyan, S., Zhu, G., Li, G., and Zhang, X. C. (2004) Refinement of the structure of human Rab5a GTPase domain at 1.05 Å resolution. Acta Crystallogr D Biol Crystallogr. 60:54-60.

  • Zhai, P., He, X., Liu, J., Wakeham, N., Zhu, G., Li, G., Tang, J., and Zhang, X. C. (2003) The interaction of the human GGA1 GAT domain with Rabaptin-5 is mediated by residues on its three-helix bundle. Biochemistry 42:13901-13908.

  • Li, G. and Qian, H. (2003) Sensitivity and specificity amplification in signal transduction. Cell Biochem. Biophy. 39:45-59.

  • Li, G., (2003) Biology can be helpful to open-minded physicists. Nature 421:111.

  • Zhu, G., Liu, J., Simon, T., Zhai, P., Li, G., and Zhang, X. C., (2003) High resolution crystal structures of human Rab5a and five mutants with substitutions in the catalytically important phosphate-binding loop. J. Biol. Chem. 278:2452-2460.

  • Li, G., (2002) GTP-binding loop. In Encyclopedia of Life Sciences. Nature Publishing Group.

  • Li, G. and Qian, H., (2002) Kinetic timing: a novel mechanism that improves the accuracy of GTPase timers in endosome fusion and other biological processes. Traffic 3:249-255.

  • Lin, J., Liang, Z., Zhang, Z., and Li, G., (2001) Membrane topography and topogenesis of prenylated Rab acceptor (PRA1). J. Biol. Chem. 276:41733-41741.

  • Li, G. and Liang, Z., (2001) Phosphate-binding loop and Rab GTPase function: mutations at Ser29 and Ala30 of Rab5 lead to loss-of-function phenotype.  Biochemical Journal 355:681-689.

  • Liang, Z. and Li, G, (2000) Mouse prenylated Rab acceptor is a novel Golgi membrane protein.  Biochem.  Biophy. Res. Comm. 275: 509-516.

  • Liang, Z., Mather, T., and Li, G., (2000) GTPase mechanism and function: new insights from systematic mutational analysis of the phosphate-binding loop residue Ala30 of Rab5. Biochem. J. 346:501-508.

  • Liu, K., and Li, G., (1998) Catalytic domain of the p120 Ras GAP binds to Rab5 and stimulates its GTPase activity. J. Biol. Chem. 273:10087-10090.

Link to full publication list >