J. Sohn, PhD

Primary Academic Title

Associate Professor of Biophysics and Biophysical Chemistry

Background

Centers and Institutes

• Basic Biomedical Sciences, Institute for
• Metabolism and Obesity Research, Center for

Additional Academic Titles

Associate Professor of Oncology, Associate Professor of Medicine

Research Interests

Use of mechanistic enzymology and X-ray crystallography to study allosterically regulated biological stress-sensors.

Lab Website

Jungsan Sohn - Lab Website

• Dr. Sohn's lab is interested in understanding how biological stress-sensors are assembled, detect danger signals and initiate stress response. Innate immunity is the first line of defense against invading pathogens in higher eukaryotes. We are using in vitro quantitative biochemical assays and mutagenesis and x-ray crystallography to investigate the underlying operating principles of inflammasomes, a component of the innate immune system, to better understand biological stress sensors.

Research Summary

Innate immunity is the first line of defense against invading pathogens in higher eukaryotes. The central players of this well-conserved form of immune response are pattern-recognition receptors (PRRs) that can recognize pathogen associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs). NOD-like receptors (NLRs) are important PRRs of innate immunity. Notably, upon binding PAMP/DAMP and nucleosie-triphosphates (NTP), NLRs assemble into multi-protein complexes called inflammasomes. The assembled inflammasomes then transduce upstream signals to directly activate procaspase-1. The activated caspase-1 then facilitates maturation of inflammatory cytokines via proteolysis. The Sohn Lab asks the following questions: What is the mechanism of inflammasome assembly? What is the mechanism of procaspase-1 activation by inflammasomes? What are the molecular mechanisms of inflammasome regulation by protein modulators?

Selected Publications

• Sohn J. and Sauer, R.T. “OMP peptides modulate the activity of DegS protease by differential binding to active and inactive conformations.” Molecular Cell. 2009; 33, 64-74.

• Sohn J., Grant R.A., Sauer R.T. “Allosteric activation of DegS, a stress sensor PDZ-protease.” Cell. 2007; 131, 572-583.

• Sohn J., Grant, R.A., Sauer, R.T. “Allostery is an intrinsic property of the protease domain of DegS: implications for enzyme function and evolution.” J. Biol. Chem. 2010; 285, 34039-47.

• Sohn J., Grant, R.A., Sauer, R.T. “OMP peptides activate the DegS protease by a relief of inhibition mechanism.” Structure. 2009; 17:1411-21.

Honors

Synergy Award, The Johns Hopkins University School of Medicine, 11/11/17

Graduate Program Affiliations

• Program in Molecular Biophysics