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Biography

Hyun-Soo Cho’s research aims to understand the structural and functional role of various proteins involved in cancer and immune diseases. He is specialized in X-ray Crystallography to solve protein structures with other biophysical and biochemical techniques including Cryo_EM recently. His ongoing research projects include various enzymes and receptors especially G-Protein Coupled Receptor (GPCR) related with cancer and immune system. 

Abstract

Recently, light-driven sodium pump rhodopsin (NaR/KR2/NDQ rhodopsin) and chloride pump rhodopsin (ClR/NTQ rhodopsin) from marine flavobacteria were identified by metagenomics study. One of them, light-driven sodium pump rhodopsin (NaR) structure was determined. The other one we have solved the first crystal structure of a unique class light-driven chloride pump (ClR) from Nonlabens marinus S1-08, at resolutions of 1.57 Å. Like structured Halorhodopsin (HR), ClR can transfer chloride ion from extracellular to cytosol. Although both ClR and HR are same light-driven chloride pump rhodopsin, we found some evidences that ClR and HR are different in structure and mechanism. The structures reveal two chloride-binding sites, one around the protonated Schiff base and the other on a cytoplasmic loop. We identify a “3 omega motif” formed by three non-consecutive aromatic amino acids that is correlated with the B-C loop orientation. Detailed CIR structural analyses with functional studies in E. coli reveal the chloride ion transduction pathway. Our results help understand the molecular mechanism and physiological role of ClR and provide a structural basis for optogenetic applications.

References:

  1. Kim K, Kwon SK, Jun SH, Cha JS, Kim H, Lee W, Kim J*, Cho HS*, Crystal structure and functional characterization of a light-driven chloride pump having an NTQ motif. Nature Communications, 7, 12677 (2016)
  2. Lim Y, Yoo J, Kim MS, Hur M, Lee EH, Hur HS, Lee JC, Lee SN, Park TW, Lee K, Chang KH, Kim K, Kang YJ, Hong KW, Kim SH, Kim YG, Yoon Y, Nam DH, Yang H, Kim DG, Cho HS*, Won J*, GC1118, an Anti-EGFR Antibody with a Distinct Binding Epitope and Superior Inhibitory Activity against High-Affinity EGFR Ligands. Molecular Cancer Therapeutics, 15, 251-263 (2016)
  3. Lee J, Choi HJ, Yun M, Kang YJ, Jung JE, Ryu Y, Kim TY, Cha YJ, Cho HS*, Min JJ*, Chung CW*, Kim HS*, Enzymatic Prenylation and Oxime Ligation for the Synthesis of Stable and Homogeneous Protein-Drug Conjugates for Targeted Therapy. ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 54, 12020-12024 (2015)
  4. Jeong SA, Kim K, Lee JH, Cha JS, Khadka P, Cho HS*, Chung IK*, Akt-mediated phosphorylation increases the binding affinity of hTERT for importin α to promote nuclear translocation. Journal of Cell Science, 128, 2287-2301 (2015)
  5. Cho YS, Yoo J, Park S, Cho HS*, The structures of the kinase domain and UBA domain of MPK38 suggest the activation mechanism for kinase activity. Acta Crystallography D, 70, 514-521 (2014)