Speakers

Physiological Responses to Biotic and Abiotic Stresses through Metalloenzymes

2
Seung Jae Lee
Chonbuk National University
Nov. 30 14:15~14:40

Abstract

Tristetraprolin (TTP) uses three cysteine and one histidine residues to bind zinc ions. TTP regulates the expression of cytokines such as tumor necrosis factor α (TNF- α) by binding to AU-rich sequence elements (AREs) located at the 3’-untranslated region (3’UTR) of the cytokines’ mRNA. Upon binding, the TTP/mRNA complex is degraded by exosomes. We have discovered that both ferric and ferrous irons will coordinate to TTP and still bind to RNA. In addition, ferrous (Fe(II)) coordinated TTP may be detrimental to the cell because it is redox active and may generate damaging reactive oxygen species (ROS).

The structure of concanavalin A (ConA) has been studied intensively due to its specific interactions with carbohydrates and its heterometal (Ca2+ and Mn2+) coordination. Biophysical studies including hydrogen/deuterium exchange (HDX) mass spectrometry and surface plasmon resonance (SPR) revealed that when the metal coordinated region of Con A, which spans Asp16 to His24, is converted to nine alanine residues (mCon ACBR), the affinity for HuNoV (GII.4) diminishes, demonstrating that this Ca2+ and Mn2+ coordinated region is responsible for the observed virus-protein interaction. The mutated carbohydrate binding region of Con A (mCon ACBR) does not affect binding affinity significantly, indicating that MCR of Con A is a major region of interaction to HuNoV (GII. 4). The results further contribute for the development of a HuNoV concentration tool, Con A-immobilized polyacrylate beads (Con A-PAB), for rapid detection of genotypes of genogroup I and II (GI and GII).

General References

  1. 1. Kim, D., Lee, H., Oh, K., Ki, A., Y., Rrotzman, R. A., Kim, D., Choi, J., Kim, M. J., Kim, S. H., Vaidya, B., Lee, S. J.*., and Kwon, J.* “Exploration of the metal coordination region of concanavalin A for its interaction with human norovirus, Biomaterials, 2017, 128, 33-43
  2. 2. Lee, S. J., Jeong, E. M., Ki, Y. A., Oh, K. S., Kwon, J., Jeong, J. H., Chung, N. J., “Oxidative defense metabolites induced by salinity stress in roots of Salicornia herbacea”, Journal of Plant Physiology, 2016, 206, 133-142
  3. 3. Lee, S. J., Michel, S. L. J. “Structural metal sites in classical and non-classical zinc finger proteins involved in transcriptional and translational regulation”, Accounts of Chemical Research, 2014, 47, 2643-2650

 

Education

  • 2005–2010, Ph.D. University of Maryland, Baltimore School of Pharmacy (Biochemistry)
  • 2000-2002, M.S. Chonbuk National University (Medicinal Chemistry)
  • 1993-2000, B.S. Chonbuk National University

 

Professional Career

  • 2017-Present, Associate Professor, Chonbuk National University
  • 2013–2017, Assistant Professor, Chonbuk National University
  • 2010-2013, Postdoctoral Fellow, MIT

 

Awards and Honors

  • 2000-Present, The Rho Chi Society, American Pharmaceutical Society
  • 2010-2013, New England Bioscience Society (NEBS)
  • 2009, Gordon Research Conference Travel Award
  • 2009, Dr. Frank J. Slams Fellowship Award, University of Maryland, School of Pharmacy
  • 2008, Department of Pharmaceutical Sciences Fellowship Award: Centennial Research Fund