Researchers

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Kwon,
Hyuk-Bang

Title:Professor
Affiliation: Department of Biology & Hormone Research Center,
Chonnam National University
Degree:Ph.D. Seoul National University, Korea
Address: Hormone Research Center, Chonnam National University, Kwangju 500-757
TEL:+82-62-530-3391
FAX:+82-62-530-0500
Email:kwonhb@chonnam.ac.kr

 

 

  Research Interest

 

 

Using native Korean frogs as experimental animals, the following projects are undergoing in our laboratory.

1) Molecular studies on the GnRH-GnRH receptor interaction

    Recently, three different types of GnRH receptor were cloned in bullfrog in this laboratory. Molecular studies on this novel GnRH receptors are undergoing ; GnRH-GnRH receptor interaction, receptor's signaling mechanism, character of three receptors, localization of these three receptors in pituitary and brain, physiological role of these novel receptors etc. Basic characters of these receptor such as binding, signaling, internalization, and dimerization were also under investigation.

2) Studies on progesterone receptor and signal transduction in oocytes

    The mechanism of the non-genomic action of progesterone on oocyte surface is being investigated. We firstly succeeded to visualize the progesterone binding to oocyte surface with confocal microscopy. We are going to clone progesterone membrane receptor genes. Recently, we found that protein kinase C and S6 kinase play a key role in progesterone induced oocyte maturation. Currently, the mechanism of S6 kinase action on oocyte maturation is being investigated.

 

  Research Fellow

 

  • Mr. Li JianHua (Lijianhua_1000@yahoo.com)
    - Ph.D. student, M.S. in school of Life Science, Zhongshan University, P.R. China
    - GnRH receptor promoter analysis
    - Screening new GnRHs and GnRH receptors in mammal
      
  • Mr. Wang Chengbing (chengbingwang@hotmail.com)
    - Ph.D. student, M.S. in school of Life Science, Zhongshan University, P.R. China
    - Localization of different types of GnRH receptor by in situ hybridization
    - Molecular mechanism of receptor action
  • Mr. Maiti Kaushik (kaishik-m@hotmail.com)
    - Ph.D. student, M.S. in Biochemistry, University of Kalyani, Calcutta, India
    - GnRH receptor signaling, receptor binding and internalization
  • Ms. Achargee Sujata (sujalaachargee@yahoo.com)
    - Ph.D. student, M.S. in Zoology, University of Kalyani, Calcutta, India
    - GnRH-GnRH receptor interaction
     
  • Ms. Oh, Dayoung (seliba@yahoo.com)
    - M.S. student, B.S. in Dept. of Biology, Chonnam National University
    - GnRH receptor signaling

 

 

  Recent Publications

 

  1. Wang C, Yun O, Maiti K, Young Oh D, Kyu Kim K, Young Seong J, Bang Kwon H. (2003) Position of Pro and Ser near Glu7.32 in the Extracellular Loop 3 of Mammalian and Nonmammalian Gonadotropin-Releasing Hormone (GnRH) Receptors is a Critical Determinant for Differential Ligand Selectivity for Mammalian GnRH and Chicken GnRH-II. Mol Endocrinol. [Epub ahead of print].
     
  2. Wang AF, Li JH, Maiti K, Kim WP, Kang HM, Seong JY, Kwon HB. (2003) Preferential ligand selectivity of the monkey type-II gonadotropin-releasing hormone (GnRH) receptor for GnRH-2 and its analogs. Mol Cell Endocrinol. 14;209(1-2):33-42.
     
  3. Maiti K, Li JH, Wang AF, Acharjee S, Kim WP, Im WB, Kwon HB, Seong JY (2003) GnRH-II analogs for selective activation and inhibition of non-mammalian and type-II mammalian GnRH receptors. Mol Cells. 31;16(2):173-179.
     
  4. Soma Chattopadhyay, Jin Hee Park, Jae Young Seong, Hyuk Bang Kwon and Keesook Lee (2003) Clonning and Characterization of Androgen Receptor from Bullfrog, Rana catesbeiana. Gen. Comp. Endocrinol. 15;134(1):10-17.
     
  5. Oh DY, Wang L, Ahn RS, Seong JY, Kwon HB (2003) Differential G protein coupling preference of mammalian and nonmammalian gonadotropin-releasing hormone receptors. Mol Cell Endocrinol 205: 89-98
     
  6. Sanyal S, Handschin C, Podvinec M, Song KH, Kim HJ, Kim JY, Seo YW, Kim SA, Kwon HB, Lee K, Kim WS, Meyer UA, Choi HS (2003) Molecular cloning and characterization of chicken orphan nuclear receptor cTR2. Gen. Comp. Endocrinol. 132(3):474-484
     
  7. Hyun Ju Lee, Yong Soo Lee, Hyuk Bang Kwon and Keesook Lee  (2003) Novel yeast bioassay system for detection of androgenic and antiandrogenic compounds. Toxicol. in Vitro 17:237-244
     
  8. Seong JY, Wang L, Oh DY, Yun O, Maiti K, Li JH, Soh JM, Choi HS, Kim K, Vaudry H, Kwon HB (2003) Ala/Thr201 in extracellular loop 2 and Leu/Phe290 in transmembrane domain 6 of type-1 frog gonadotropin-releasing hormone receptor confer differential ligand sensitivity and signal transduction. Endocrinology 144:454-466 
     
  9. Kwang-Hoon Song, Tae-Moon Kim, Han-Jong Kim, Jung Woo Kim, Hong-Hee Kim, Hyuk-Bang Kwon, Won Sun Kim, and Hueng-Sik Choi. (2003) Molecular cloning and characterization of a novel inhibitor of apoptosis protein from Xenopus laevis. Biochem.Biophys.Res.Com. 301:236-242 
     
  10. Acharjee S, Maiti K, Soh JM, Im WB, Seong JY, Kwon HB (2002) Differential desensitization and internalization of three different bullfrog gonadotropin-releasing hormone receptors. Mol Cells 14:101-107 
     
  11. Seo YW, Sanyal S, Kim HJ, Won DH, An JY, Amano T, Zavacki AM, Kwon HB, Shi YB, Kim WS, Kang H, Moore DD and Choi HS. (2002) FOR, a novel orphan nuclear receptor related to FXR. J.Biol.Chem. 277:17836-17844
     
  12. Jung-Won Ju, Arun Bandyopadhyay, Wook-Bin Im, Jongkyung Chung, Hyuk Bang Kwon and Hueng-Sik Choi (2002) Involvement of Phosphatidylinositol 3 kinase in the progesterone-induced oocyte maturation in Rana dybowskii. Gen.and Comp.Endocrinol. 126:213-220
     
  13. Wang L, Oh DY, Bogerd J, Choi HS, Ahn RS, Seong JY, Kwon HB (2001) Inhibitory activity of alternative splice variants of the bullfrog GnRH receptor-3 on wild-type receptor signaling. Endocrinology. 142(9):4015-4025
     
  14. Wang L, Bogerd J, Choi HS, Seong JY, Soh JM, Chun SY, Blomenrohr M, Troskie BE, Mi RP, Yu WH, McCann SM, Kwon HB (2001) Three distinct types of GnRH receptor characterized in the bullfrog. Proc Natl Acad Sci USA, 98(1):361-366
     
  15. Ha CM, Kang JH, Choi EJ, Kim MS, Park JW, Kim Y, Choi WS, Chun SY, Kwon HB, Lee BJ (2000) Progesterone increases mRNA levels of pituitary adenylate cyclase-activatin polypeptide (PACAP) and type I PACAP receptor (PAC(1)) in the rat hypothalamus. Brain Res Mol Brain Res, 78(1-2):59-68
     
  16. Wang L, MS Yoo, HM Kang, WB Im, HS Choi, J Bogerd, HB Kwon (2000) Cloning and characterization of cDNAs encoding the GnRH1 and GnRH2 precursors from bullfrog (Rana catesbeiana). J. Exp. Zool., 289:190-201
     
  17. Yoo MS, Kang HM, Choi HS, Kim JW, Troskie BE, Millar RP and Kwon HB (2000) Molecular cloning, distribution and pharmacological characterization of a novel gonadotropin-releasing hormone([Trp8] GnRH) in frog brain. Mol. Cell. Endocrinol. 164:197-204

  18. Koh PO, Kwak SD, Kang SS, Cho GJ, Chun SY, Kwon HB, Choi WS (2000) Expression of pituitary adenylate cyclase activating polypeptide (PACAP) and PACAP type I A receptor mRNAs in granulosa cells of preovulatory follicles of the rat ovary. Mol Reprod Dev. 55(4):379-86
     
  19. Park JI, Kim WJ, Wang L, Park HJ, Lee J, Park JH, Kwon HB, Tsafriri A, Chun SY (2000) Involvement of progesterone in gonadotrophin-induced pituitary adenylate cyclase-activating polypeptide gene expression in pre-ovulatory follicles of rat ovary.
    Mol Hum Reprod. 6(3):238-245
     
  20. Park HJ, Lee J, Wang L, Park JH, Kwon HB, Arimura A, Chun SY (2000)  Stage-specific expression of pituitary adenylate cyclase-activating polypeptide type I receptor messenger ribonucleic acid during ovarian follicle development in the rat.
    Endocrinology. 141(2):702-9
     
  21. Bandyopadhyay J, Bandyopadhyay A, Choi HS, Kwon HB, Kang HM (2000) Cloning and characterization of cDNA encoding cdc2 kinase, a component of maturation-promoting factor, in Rana dybowskii. Gen Comp Endocrinol. 117(2):313-22
     
  22. Ahn RS, Yoo MS, Kwon HB (1999) Evidence for two-cell model of steroidogenesis in four species of amphibian. J. Exp. Zool. 284:91-99
     
  23. Lee, H.K., M.S. Yoo, H.S. Choi, H.B. Kwon, J. Soh (1999) Retinoic acids up-regulate steroidogenic acute regulatory protein gene. Mol. Cell. Endocrinol. 148:1-10
     
  24. Bandyopadhyay A., J. Bandyopadhyay, J Chung, H.S. Choi, H.B. Kwon (1999) Inhibition of S6 kinase by rapamycin blocks maturation of Rana dybowskii oocytes. Gen. Comp. Endocrinol. 113:230-239
     
  25. Lee J., H.J. Park, H.S. Choi, H.B. Kwon, A. Aeimura, B.J. Lee, W.S. Choi, S.Y. Chun (1999) Gonadotropin stimulation of pituitary adenylate cyclase-activating polypeptide (PACAP) messenger ribonucleic acid in the rat ovary and the role of PACAP as a follicle survival factor. Endocrinology. 140:818-826
     
  26. Kim M.Y., H.K. Lee, J.S. Park, S.H., Park, H.B. Kwon, J. Soh (1999) Identification of a zeta-crystallin (quinone reductase)-like 1 gene (CRYZL1) mapped to human chromosome 21q22.1. Genomics 57:156-159
     
  27. Seong, J.Y., S.S. Kang, K. Kam, Y.G. Han, H.B. Kwon, K. Ryu, K. Kim (1998) Differential regulation of gonadotropin-releasing hormone (GnRH) receptor expression in the posterior mediobasal hypothalamus by steroid hormones: implication of GnRH neuronal activity. Mol. Brain Res. 53:226-235
     
  28. Kim J.W., W.B. Im, H.H. Choi, S. Ishii, H.B. Kwon (1998) Seasonal fluctuations in pituitary gland and plasma levels of gonadotropin hormones in Rana. Gen. Comp. Endocrinol. 109:13-23
     
  29. Bandyopadhyay, A., J. Bandyopadhyay, H.H. Choi, H.S. Choi, H.B. Kwon (1998) Plasma membrane mediated action of progesterone in amphibian (Rana dybowskii) oocyte maturation. Gen. Comp. Endocrinol. 109:293-301
     
  30. Lee, H.K., Y.K. Lee, S.H. Park, Y.S. Kim, S.H. Park, J.W. Lee, H.B. Kwon, J. Soh, D.D. Moore, H.S. Choi (1998) Structure and expression of the orphan nuclear receptor SHP gene. J. Biol. Chem. 273:14398-14402
     
  31. Ko, S.K., H.M. Kang, W.B. Im, H.B. Kwon (1998) Testicular cycles in three species of Korean frogs: Rana nigromaculata, Rana rugosa, and Rana dybowskii. Gen. Comp. Endocrinol. 111:347-358
     
  32. Sirotkin, A.V. A.V. Makarevich, J. Kotwica, P.G. Marnet, H.B. Kwon, L. Hetenyi (1998) Isolated procine ovarian follicles as a model for the study of hormone and growth factor action on ovarian secretory activity. J. Endocrinol. 159:313-321
     
  33. Kang, S.S., G.H. Son, J.Y. Seong, D. Choi, H.B. Kwon, C.C. Lee, K. Kim (1998) Noradrenergic neurotoxin suppresses gonadotropin-releasing hormone (GnRH) and GnRH receptor gene expression in ovariectomized and steroid-treated rats. J Neuroendocrinoloy 10:911-918
     
  34. Cho, S.H., J. Han, W. Sun, D. Choi, H.B. Kwon, H. Jarry, W. Wuttke, K. Kim (1997) Evidence for autocrine inhibition of gonadotropin-releasing hormone (GnRH) in hypothalamus GT1-1 neuronal cells. Mol. Brain Res. 50:51-58
     
  35. Chang, K.J., J.W. Kim, W.B. Im, H.M. Kang, H.B. Kwon (1997) Differential effects of gonadotropin and orthovanadate on oocyte maturation, ovulation and prostaglandin synthesis by Rana ovarian follicles in vitro. J. Exp. Zool. 277:155-165
     
  36. Shim, C., D. Choi, H.B. Kwon, K. Kim (1997) Expression of laminin chain-specific gene transcripts in mouse uterine tissues during peri-implantation period. Mol. Reprod. Dev. 48:176-184
     
  37. Lee H.K., R.S. Ahn, H.B. Kwon, J. Soh (1997) Nucleotide sequence of rat steroidogenic acute regulatory protein complementary DNA. Biochem. Biophys. Res. Commun. 230:528-532
     
  38. Kim M.Y., H.B. Kwon, J. Soh (1997) Characterization of four yeast artificial chromosone clones mapped to human chromosome 21q22.1 with eight markers. Mol. Cells 31:526-31
     
  39. Shim, C., H.B. Kwon, K. Kim (1996) Differential expression of laminin chain-specific mRNA transcripts during mouse preimplantation embryo development. Mol. Reprod. Dev. 44:44-55
     
  40. Chang, K.J., J.W. Kim, J. Lee, W.B. Im, H.B. Kwon and A.W. Schuetz (1995) Prostaglandin production and ovulation during exposure of amphibian ovarian follicles to gonadotropin or phorbol ester in vitro. Gen. Comp. Endocrinol. 100:257-266
     
  41. Kwon, H.B., and R.S. Ahn (1994) Relative roles of theca and granulosa cells in ovarian follicular steroidogenesis in the amphibians, Rana nigromaculata. Gen. Comp. Endocrinol. 94:207-214
     
  42. Kwon, H.B., R.S. Ahn, W.K. Lee, W-B. Im, and K. Kim (1993) Changes in the activities of steroidogenic enzymes during the development of ovarian follicles in Rana nigromaculata. Gen. Comp. Endocrinol. 92:225-232
     
  43. Ahn, R.S., S.K. Ko, D.G. Bai, Y.D. Yoon, and H.B. Kwon (1993) Steroidogenic shift by cultured ovarian follicles of Rana dybowskii at breeding season. J. Exp. Zool. 267:275-282

 
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