Expression of MEK1 Fusion Protein in Yeast for Developing Cell Based Assay System, a Major Substrate of LeTx

Yeast내에서 MEK1 융합 단백질 발현 및 Lethal Factor 활성 검증

  • Hwang, Hye-Hyun (Department of Chemistry, College of Natural Sciences, Hanyang University) ;
  • Kim, Joung-Mok (Department of Chemistry, College of Natural Sciences, Hanyang University) ;
  • Choi, Kyoung-Jae (Department of Chemistry, College of Natural Sciences, Hanyang University) ;
  • Park, Hae-Chul (Department of Chemistry, College of Natural Sciences, Hanyang University) ;
  • Han, Sung-Hwan (Department of Chemistry, College of Natural Sciences, Hanyang University) ;
  • Chung, Hoe-Il (Department of Chemistry, College of Natural Sciences, Hanyang University) ;
  • Koo, Bon-Sung (Microbial Function Team, National Institute of Agricultural Biotechnology, RDA) ;
  • Park, Joon-Shik (NANO Mechatronics Research Center, Korea Electronics Technology Institute) ;
  • Yoon, Moon-Young (Department of Chemistry, College of Natural Sciences, Hanyang University)
  • Published : 2006.09.30

Abstract

Lethal toxin is a critical virulence factor of anthrax. It is composed two protein: protective antigen (PA) and lethal factor (LF). PA binds to specific cell surface receptors and, forms a membrane channel that mediates entry of LF into the cell. LF is a zinc-dependent metalloprotease, which cleaves MKKs [MAPK (mitogen-activated protein kinase) kinases] at peptide bonds very close to their N-termini. In this study, we suggest application of cell-based assays in the early phase of drug discovery, with a particular focus on the use of yeast cells. We constructed MEK1 expression system in yeast to determine LF activity and approached cell-based assay system to screen inhibitors, in which the results covering the construction of LF-substrate in yeast expression vector, expression, and LF-mediated proteolysis of substrate were described. These results could provided the basic steps in design of cell-based assay system with the high efficiency, rapidly and easy way to screening of inhibitors.

Anthrax lethal toxin은 탄저병의 치사원인이 되는 독소이며, Lethal toxin은 두 종류의 단백질 PA (Protective antigen)과 LF (lethal factor)로 구성되어 진다. PA는 세포표면의 수용체와 결합하여 LF를 세포질 안으로 이동시켜 주는 역할을 한다. LF는 금속 이온$(Zn^{2+})$ 의존적 단백질 가수분해 효소로써 MKKs[MAPK (mitogen-activated protein kinase) kinases] 집단 단백질의 아미노 말단 부분을 절단하여 대상 세포를 죽음으로 유도하는 것으로 알려져 있다. 본 연구에서는 LF에 대한 특성 분석 및 억제제 개발에 과한 연구를 위해 cell-based high-throughtput screens 개발에 선행되어야 하는 기초 자료를 마련하는데 그 목적이 있다. 이를 위하여 LF의 절단 대상이 되는 기질이 MEK1을 yeast내에서 동시 발현시켜 LF의 활성을 검증하였다. 먼저 효모(Saccharomyces cerevisiae)를 숙주로 하여 LF의 기질인 MEK1 발현 vector를 구축하였고, 구축된 발현 system을 기본을 LF 활성을 검증하고자 yeast에 형질전환하여 plasmid의 안전성 및 MEK1 유전자의 발현 및 LF에 의한 MEK1 아미노말단의 절단 부위를 확인하였다. 본 연구는 세포내 검증 system 도입의 기초적 자료를 제공하였으며, yeast내의 MEK1 발현은 탄저병의 저해제 선별 및 활성 측정 검증을 생체에서 고효율적이며, 안정적으로 할 수 있다는 가능성을 나타냈다.

Keywords

References

  1. 황혜현, 김정목, 최경재, 정회일, 한성환, 구본성, 윤문영. 2005. Yeast 내에서 탄저병 원인균인 Bacillus anthracis의 치사독소인 Lethal Factor 단백질 발현. 미생물학회지 41, 275-280
  2. Agrawal, A., J. Lingappa, S.H. Leppla, S. Agrawal, A. Jabbar, C. Quinn, and B. Pulendran. 2003. Impairment of dentritic cells and adaptive immunity by anthrax lethal toxin. Nature 424, 329-334 https://doi.org/10.1038/nature01794
  3. Bardwell, A.J., L.J. Flatauer, K. Matsukuma, J. Thormer, and L. Bardwell. 2001. A conserved docking site in MEKs mediates high-affinity binding to MAP kinases and cooperates with a scaffold protein to enhance signal transmission. J. Biol. Chem. 276, 10374-10386 https://doi.org/10.1074/jbc.M010271200
  4. Beauregard, K.E., R.J. Collier, and J.A. Swanson. 2000. Proteolytic activation of receptor-bound anthrax protective antigen on macrophages promotes its internalization. Cell Microiol. 2, 251-258 https://doi.org/10.1046/j.1462-5822.2000.00052.x
  5. Burke, D., D. Dawson, and T. Stearns. 2000. Methods in yeast genetics. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y
  6. Collier, R.J. and J.A. Young. 2003. Anthrax toxin. Annu. Rev. Cell Dev. Biol. 19, 45-70 https://doi.org/10.1146/annurev.cellbio.19.111301.140655
  7. Dixon, T.C., M. Meselson, J. Guillemin, and P.C. Hanna. 1999. Anthrax. Engl. J. Med. 341, 815-826 https://doi.org/10.1056/NEJM199909093411107
  8. Dong, C., R.J. Kavis, and R.A. Flavell. 2002. MAP kinases in the immune response. Annu. Rev. Immunol. 20, 55-72 https://doi.org/10.1146/annurev.immunol.20.091301.131133
  9. Drum, C.L., S.Z. Yan, J. Bard, Y.Q. Shen, D. Lu, S. Soelaiman, Z. Grabarek, A. Bohm, and W.J. Tang. 2002. Structural basis for the activation of anthrax adenylyl cyclase exotoxin by calmodulin. Nature 415, 396-402 https://doi.org/10.1038/415396a
  10. Duesery, N.S., C.P. Webb, S.H. Leppla, V.M. Gordon, K.R. Klimpel, T.D. Copeland, N.G. Ahn, M.K. Oskarsson, K. Fukasawa, K.D. Paull, and C.F. Bande Woude. 1998. Protolytic inactivation of MAP-Kinase-kinase by anthrax lethal factor. Science 280, 734-737 https://doi.org/10.1126/science.280.5364.734
  11. Ezzell, J.W. and T.G. Abshire. 1988. Immunological analysis of cell associated antigens of Bacillus anthracis. Infect. Immun. 56, 349-356
  12. Gietz, D., A.St. Jean, T.A. Woods, and T.H. Schiestl. 1992. Improved method for high efficiency transformation of intact yeast cells. Nucleic Acids Res. 20, 1425 https://doi.org/10.1093/nar/20.6.1425
  13. Grossier, F. and M. Mock. 2001. Toxins of Bacillus anthracis. Toxicon. 39, 1747-1755 https://doi.org/10.1016/S0041-0101(01)00161-1
  14. Klimpel, K.R., S.S. Molloy, G. Thomas, and S.H. Leppla. 1992. Anthrax toxin protective antigen is activated by a cell surface protease with the sequence specificity and catalytic properties of furin. Proc. Natl. Acad. Sci. USA. 89, 10277-10281 https://doi.org/10.1073/pnas.89.21.10277
  15. Leppla, S.H. 1988. Production and purification of anthrax toxin, in: Methods in Enzymology. Academic press. 165, 103-116
  16. Mock, M. and A. Fouet. 2001. Anthrax. Annu. Rev. Microbiol. 55, 647-671 https://doi.org/10.1146/annurev.micro.55.1.647
  17. Mogridge, J., K. Cunningham, and R.J. Collier. 2002. Stoichiometry of anthrax toxin complexes. Biochemistry. 41, 1079-1082 https://doi.org/10.1021/bi015860m
  18. Morton, N. and M.D. Swartz. 2001. New Engl. J. Med. 345, 1621- 1626 https://doi.org/10.1056/NEJMra012892
  19. Pellizzari, R., C. Guidi-Rontani, G. Vitale, M. Mock, and C. Montecucco. 1999. Anthrax lethal factor cleaves MKK3 in macrophages and inhibit the LPS/IFN$\gamma$- induced release of NO and TNF$\alpha$.FEBS Lett. 462, 199-204 https://doi.org/10.1016/S0014-5793(99)01502-1
  20. Vitale, G., L. Bernardi, G. Napolitani, M. Mock, and C. Montecucco. 2000. Susceptibility of mitogen-activated protein kinase kinase family members to proteolysis by anthrax lethal factor. Biochem. J. 352, 739-745 https://doi.org/10.1042/0264-6021:3520739
  21. Vitale, G., R. Pellizzari, C. Recchi, G. Napolitani, M. Mock, and C. Montecucco. 1998. Anthrax lethal factor cleaves the N-terminus of MAPKKs and induces tyrosine/threonine phosphorylation of MAPKs in cultured macrophages. Biochem. Biophys. Res. Commun. 38, 706-711
  22. Xu, B., S. Stippec, F.L. Rovinson, and M.H. Cobb. 2001. Hydrophobic as well as charged residues in both MEK1 and ERK2 are important for their proper docking. J. Biol. Chem. 276, 26509- 26515 https://doi.org/10.1074/jbc.M102769200