Biochemistry

Biochemistry Laboratory - Prof. Choe Hui-Woog

The structure-function relationship of proteins is one of the key research fields in biochemistry.
My research field is X-ray protein crystallography. Many milligrams of purified proteins are in general prerequisite for growing the X-ray suitable crystals. Everybody in our lab. therefore starts to purify proteins in which one is interested. The source can be directly from bacteria, plants and/or animals.
Mostly we are using the recombinant proteins for purifying large quantity of materials which have been expressed in Escherchia coli and/or in yeast. Crystallization is a bottleneck for 3D structure determination of proteins. When one has got a success to grow for X-ray suitable protein crystals, the next step will be data collection usually using Synchrotron X-ray source. There are many programs to calculate the density maps from collected data. From the refined density maps the final model of a 3D structure can be represented. I am interested in the structure determination of membrane proteins which are involved in the visual signal transduction.

REPRESENTATIVE PUBLICATIONS

1. Choe HW, Kim YJ, Park JH, Morizumi T, Pai EF, Krauss N, Hofmann KP, Scheerer P, Ernst OP. Crystal structure of metarhodopsin II. Nature 471, 651-655 (2011)
2. Scheerer P, Park JH, Hildebrand PW, Kim YJ, Choe HW, Hofmann KP, Ernst OP. Crystal structure of opsin in its G protein-interacting conformation. Nature 455, 497-502 (2008)
3. Park JH, Scheerer P, Hofmann KP, Choe HW, Ernst OP. Crystal structure of the ligand-free G-protein-coupled receptor opsin. Nature 454, 183-187 (2008)
4. Granzin J, Wilden U, Choe HW, Labahn J, Kraft B, Buldt G. X-ray crystal structure of arrestin from bovine rod outer segments. Nature 391, 918-921 (1998)
5. Kostrewa D, Granzin J, Koch C, Choe HW, Raghunathan S, Wolf W, Labahn J, Kahmann R, Saenger W.Three-dimensional structure of the E.coli DNA-binding protein FIS. Nature 349, 178-180 (1991)

Plant Biochemistry Laboratory - Prof. Seo Pil-Joon

Plants are sessile organisms and thus have to endure environmental challenges. They have developed sophisticated mechanisms to deal with their environment. We are interested in elucidating the molecular mechanisms underlying plant responses to environmental stresses. We use a combination of genetic, biochemical, genomic and proteomic approaches to analyze various levels of gene regulation (chromatin level/epigenetic, transcriptional, posttranscriptional, and protein turnover) and to understand stress signaling and stress tolerance. Our long-term goals are to elucidate the signaling networks used by plants in responding to environmental stresses and to identify key genes for regulating the responses of plants to environmental stresses which ultimately will lead to major contributions to agriculture and the environment.

1. Seo PJ, Park MJ, Lim MH, Kim SG, Lee M, Baldwin IT, Park CM. (2012) A self-regulatory circuit of CIRCADIAN CLOCK-ASSOCIATED 1 underlies the circadian clock regulation of temperature responses in Arabidopsis. Plant Cell 24: 2427-2442.
2. Seo PJ, Kim MJ, Ryu JY, Jeong EY, Park CM. (2011) Two splice variants of the IDD14 transcription factor competitively form nonfunctional heterodimers which may regulate starch metabolism. Nat. Commun. 2: 303.
3. Seo PJ, Hong SY, Kim SG, Park CM. (2011) Competitive inhibition of transcription factors by small interfering peptides. Trends Plant Sci. 16: 541-549.
4. Seo PJ, Lee SB, Suh MC, Park MJ, Go YS, Park CM. (2011) The MYB96 transcription factor regulates cuticular wax biosynthesis under drought conditions in Arabidopsis. Plant Cell 23: 1138-1152.
5. Seo PJ, Kim SG, Park CM. (2008) Membrane-bound transcription factors in plants. Trends Plant Sci. 13: 550-556.