Department of Chemistry and Biochemistry

Cellular redox agents contribute to a plethora of both physiological and pathophysiological processes as they can promote DNA damage as well as oxidative inactivation or activation of certain redox-active proteins. Our research efforts focus on elucidating the mechanisms by which (i) redox-active small GTPases, including the proto-oncoprotein p21Ras (Ras), and (ii) redox-active phosphatases are regulated by redox agents.

"Insight into the 6-thiopurine-mediated Termination of the Invasive Motility of Tumor Cells Derived From Inflammatory Breast Cancer" Jongyun Heo, Michael Wey, and Inpyo Hong, Biochemistry, (2011) 50: 5731-5742.

"Redox Control of GTPases: From Molecular Mechanism to Functional Significance in Health and Disease" Jongyun Heo Antioxidants & Redox Signaling, (2011) 14; 689-724.

"Ras-targeting Action of Thiopurines in the Presence of Reactive Nitrogen Species" Jongyun Heo and Inpyo Hong, Biochemistry, (2010) 49; 3965-3976.

"The control of S-thiolation by cysteine via gamma-glutamyltranspeptidase and thiol exchanges in erythrocytes and plasma of diamide-treated rats" Raffaella Priora, Lucia Coppo, Antonios Margaritis, Danila Di Giuseppe, Simona Frosali, Domenico Summa, Jongyun Heo, and Paolo Di Simplicio, Toxicology and Applied Pharmacology, (2010) 242; 333-343.

"Redox regulation of Ran GTPase" Jongyun Heo, Biochem. Biophys. Res. Commun. 2008, 376, 568-572.

"Redox regulation of RhoA" Jongyun Heo, Kimberly W. Raines and Sharon L. Campbell, Biochemistry 2006, 45, 14481-14489.

"Ras Regulation by Reactive Oxygen and Nitrogen Species" Jongyun Heo and Sharon L. Campbell, Biochemistry 2006, 45, 2200-2210.

"Nitirc Oxide and Cell Signaling: Redox Regulation of Ras Superfamily GTPases" Jongyun Heo and Sharon L. Campbell, in Nitric Oxide, Cell Signaling, and Gene Expression, Santiago Lamas and Enrique Cadenas, Eds., Taylor & Francis Group, LLC., New York (2005).

"Mechanism of Redox-Mediated Guanine Nucleotide Exchange on Redox-Active Rho GTPases" Jongyun Heo and Sharon L. Campbell, J. Biol. Chem. 2005, 280, 31003-31010.

"Recognition and Activation of Rho GTPases By Vav1 and Vav2 Guanine Nucleotide Exchange Factors" Jongyun Heo, Roopa Thapar and Sharon L. Campbell, Biochemistry 2005, 44, 6573-6585.

"Superoxide Anion Radical Modulates the Activity of Ras and Ras-Related GTPases by a Radical-Based Mechanism Similar to that of Nitric Oxide" Jongyun Heo and Sharon L. Campbell, J.  Biol. Chem. 2005, 280, 12438-12445.

"Mechanism of Free Radical Nitric Oxide-Mediated Ras Guanine Nucleotide Dissociation" Jongyun Heo, Kirk C. Prutzman, Viorel Mocanu and Sharon L. Campbell, J. Mol. Biol. 2005, 346, 1423-1440.

"pH-Dependent Perturbation of Ras Guanine-Nucleotide Interactions and Ras-Guanine-Nucleotide Exchange" Jongyun Heo, Guanghua Gao and Sharon L. Campbell, Biochemistry 2004, 43, 10102-10111.

"Mechanism of p21Ras S-Nitrosylation and Kinetics of Nitric Oxide-Mediated Guanine Nucleotide Exchange" Jongyun Heo and Sharon L. Campbell, Biochemistry 2004, 43, 2314-2322.

"Converting the NiFeS Carbon Monoxide Dehydrogenase to a Hydrogenase and a Hydroxylamine Reductase" Jongyun Heo, Marcus T. Wolfe, Christopher R. Staples and Paul W. Ludden, J. Bacteriol. 2002, 184, 5894-5897.

"Hydroxylamine Reductase Activity of the Hybrid Cluster Protein from Escherichia coli" Marcus T. Wolfe, Jongyun Heo, John S. Garavelli and Paul W. Ludden, J. Bacteriol. 2002, 184, 5898-5902.

"CO Dehydrogenase from Rhodospirillum rubrum Produces Formate" Jongyun Heo, Lars Skjeldal and Paul W. Ludden, J. Biol. Inorg. Chem. 2002, 7, 810-814.

"Life on Carbon Monoxide: X-Ray Structure of Rhodospirillum rubrum Ni-Fe-S Carbon Monoxide Dehydrogenase at 2.8 Å Resolution" Catherine L. Drennan, Jongyun Heo, Michael D. Sintchak, Eric Schreiter and Paul W. Ludden, Proc. Natl. Acad. Sci. U. S. A. 2001, 98, 11973-11978.

"Redox-Dependent Activity of CO Dehydrogenase from Rhodospirillum rubrum" Jongyun Heo, Cale M. Halbleib and Paul W. Ludden, Proc. Natl. Acad. Sci. U. S. A. 2001, 98, 7690-7693.

"The Redox-Dependent CO2 Reduction Activity of CO Dehydrogenase from Rhodospirillum rubrum" Jongyun Heo, Christopher R. Staples and Paul W. Ludden, Biochemistry 2001, 40, 7604-7611.

"Evidence for a CO Ligand in CO-Dehydrogenase from Rhodospirillum rubrum that is Required for Catalytic Activity" Jongyun Heo, Christopher R. Staples, Cale M. Halblieb and Paul W. Ludden, Biochemistry 2000, 39, 7956-7963.

"Rhodospirillum rubrum CO-Dehydrogenase (Part 2).  Spectroscopic Investigation and Assignment of Spin-Spin Coupling Signals" Jongyun Heo, Christopher R. Staples, Joshua Telser and Paul W. Ludden, J. Am. Chem. Soc, 1999, 121, 11045 -11057.

"Rhodospirillum rubrum CO-Dehydrogenase (Part 1).  Spectroscopic Studies of CODH Variant C531A Indicate the Presence of a Binuclear [FeNi] Cluster" Christopher R. Staples, Jongyun Heo, Nathan J. Spangler, Robert L. Kerby, Gary P. Roberts and Paul W. Ludden, J. Am. Chem. Soc, 1999, 121, 11034 -11044.

"Regulation of 2-Carboxy-D-Arabinitol 1-Phosphatase: Activation by Glutathione and Interaction with Thiol Reagents" Jongyun Heo and Gabriel P. Holbrook, Biochem. J. 1999, 338, 409-416.

"Progress Toward the X-ray Structure Determination of R. rubrum Carbon Monoxide Dehydrogenase" Catherine L. Drennan, Nathan J. Spangler, Jongyun Heo, Paul W. Ludden and Douglas C. Rees, J. Inorg. Biochem. 1999, 74 (1-4), 118.

"Characterization of Rhodospirillum rubrum CO-Dehydrogenase" Christopher R. Staples, Jongyun Heo, Nathan J. Spangler, Robert L. Kerby, Gary P. Roberts and Paul W. Ludden, J. Inorg. Biochem. 1999, 74 (1-4), 304.

B.Sc. Sogang University, Seoul, Korea (1987)

M.Sc. Northern Illinois University (1997)

Ph.D.  University of Wisconsin-Madison, (2001)

Postdoctoral Fellow:
University of North Carolina-Chapel Hill  (2001-2006)