Professor School of Molecular Biosciences Washington State University Pullman, WA 99164-4234   Phone: 509-335-7022 FAX: 509-335-1907 E-mail: khkim@mail.wsu.edu    Ph.D., 1982 Princeton University RESEARCH INTERESTS: Testis Biology/Reproductive Toxicology RESEARCH SUMMARY: The primary goal of my research is to understand the molecular and cellular mechanisms controlling embryonic and postnatal testis development and sperm production. A current focus is to determine the role of vitamin A (retinoids) and retinoid receptors in testicular cells in which both vitamin A and retinoid receptors have been shown to be essential for normal function. For example, vitamin A-deficient animals and transgenic mice carrying a mutated retinoid receptor gene are both sterile. Related to this, we are also interested to determine the mechanism by which environmental toxins, also referred to as endocrine disruptors, interfere with normal retinoid signaling in the testis, resulting in abnormal testis development and reduced sperm production. To do this work, we use state-of-the art molecular and cellular techniques and in vivo animal model systems such as developing rats, environmental toxin- or vitamin A-deprived rats, and transgenic receptor knockout mice. Specific projects include: (1) identification of the mechanisms by which retinoid receptors are activated, (2) identification of the proteins directly induced by these receptors which are essential for testis function, and (3) identification of abnormal retinoid signaling mechanisms produced during exposure to environmental toxins. REPRESENTATIVE PUBLICATIONS: Bhattacharya N, Vo M-N, Dufour JM, Okita JR, Okita RT, Kim KH (2005). Differential effects of phthalates on the testis and liver. Biol Reprod; 72:745-754. Li H, Kim KH (2004). Retinoic acid inhibits rat XY gonad development by blocking mesonepheric cell migration and decreasing the number of gonocytes. Biol Reprod; 70:687-693. Li H, Kim KH (2003). Effects of mono- (2-ethylhexyl) phthalate on fetal and neonatal rat testes in organ cultures. Biol Reprod; 2003; 69:1964-1972. Li H, Kim KH (2003). Effects of ethanol on embryonic and neonatal rat testes in organ cultures. J Andro; 24:653-660 Dufour JM, Vo MN, Bhattacharya N, Okita J, Okita R, Kim KH (2002). Peroxisome proliferators disrupt retinoic acid receptor alpha signaling in the testis. Biol Reprod; 68:1215-24. Braun KW, Vo M-N, Kim KH (2002). Positive regulation of retinoic Acid receptor alpha by protein kinase C and mitogen-activated protein kinase in sertoli cells. Biol Reprod; 67:29-37. Braun, K., Tribley, W., Griswold, M.D., and Kim, K.H. (2000) Regulation of the retinoic acid receptor alpha (RARµ) signaling by protein kinase A in mouse Sertoli cell lines. J. Bio Chem. 275:4145-4151. Dufour, J. M. and K. H. Kim (1999). Cellular localization of six retinoid receptors in rat testis during postnatal development: Identification of potential heterodimeric receptors. Biol. Reprod. 61, in press (Nov). Cupp , A.S., J.M. Dufour, G. Kim, M.K. Skinner, K. H. Kim (1999). Action of retinoids on embryonic and early postnatal testis development. Endocrinology 140, 2343-2352. Akmal, K. M., J. M. Dufour, M. Vo, S. Higginson, and K. H. Kim (1998). Ligand-dependent regulation of retinoic acid receptor a in rat testis: in vivo response to depletion and repletion of vitamin A. Endocrinology, 139, 1239-1248. Akmal, K. M., J. Dufour, and K. H. Kim (1997). Retinoic acid receptor-a gene expression in the rat testes: Potential role during the prophase of meiosis and in the transition from round to elongating spermatids. Biol. Reprod. 56, 549-556. Akmal, K.M., J. Dufour, and K.H. Kim (1996). Region-specific localization of retinoic acid receptor-a expression in the rat epididymis. Biol. Reprod. 54:1111-1119.