Nobuaki Kikyo, M.D./Ph.D.

kikyo001@umn.edu

Education

Dr. Kikyo is Associate Professor of Medicine and a member of the Stem Cell Institute andthe Masonic Cancer Center.  He received his M.D. in 1987 and Ph.D. in 1993 from Tokyo University Medical School, Japan.  He studied genomic imprinting in Dr. Azim Surani’s laboratory at Wellcome/CRC Institute, University of Cambridge as a postdoctoral fellow. He then moved to Dr. Alan Wolffe’s laboratory at NIH to start biochemical analysis of somatic cell nuclear cloning in Xenopus.  He joined the University of Minnesota in 2000.

Research Interests

The long-term goal of Dr. Kikyo's group is to understand molecular mechanisms of pluripotency and cell differentiation.  Once these mechanisms are understood, they can be applied to transplantation medicine to create new tissues using a patient's own somatic cells instead of ethically controversial embryonic materials.  His group has been using somatic cell nuclear cloning in Xenopus and induced pluripotent stem cells (iPSCs) of mouse and human to investigate pluripotency. His group established an in vitro model of Xenopus nuclear cloning by incubating egg extract and somactic cell nuclei.  From this study, they identified the SWI/SNF ATPase ISWI, the nucleolar disassembly proteins FRGY2a/b, and the histone chaperon nucleoplasmin as key proteins for nuclear remodeling in nuclear cloning.  More recently, Dr. Kikyo's group fused the powerful transactivation domain of MyoD to Oct4 and radically improved the efficiency of making iPSCs.  His group continues the search for other key regulators needed for the acquisition of pluripotency in somatic cells.

Selected Biography

• Hirai, H., Karian, P., and Kikyo, N. (2011) Regulation of embryonic stem cell self-renewal and pluripotency by leukemia inhibitory factor. Biochemical J 438: 11-23.
• Hirai, H., Tani, T., Katoku-Kikyo, N., Kellner, S., Karian, P., Firpo, M., and Kikyo, N. (2011) Radicl acceleration of nuclear reprogramming by chromatin remodeling with the transactivation domain of MyoD. Stem Cells 29: 1349-61.
• Hirai, H., Tani, T., and Kikyo, N. (2010) Structure and functions of powerful transactivators: VP16, MyoD, and FoxA. Int'l J Dev Biol 54: 1589-96.
• Hirai, H., Romanova, L., Kellner, S., Verma, M., Rayner, S., Asakura, A. and Kikyo, N. (2010) Post-mitotic role of mucleostemin as a promoter of skeletal muscle cell differentiation. Biochem Biophys Res Comm 391: 299-304.
• Kellner, S. and Kikyo, N. (2010) Transcriptional regulation of the Oct4 gene, a master gene for pluripotency. Histology and Histopathology 25: 405-12
• Romanova, L., Katoku-Kikyo, N., Kellner, S. and Kikyo, N. (2009) Novel role of nucleostemin in the maintenance of nucleolar architecture and integrity of small nucleolar ribonucleoproteins and the telomerase complex.  J Biol Chem 284: 26685-94.
• Romanova, L., Grand, A., Zhang, L., Rayner, S., Katoku-Kikyo, N., and Kikyo, N. (2009) Critical role of nucleostemin in pre-rRNA processing and protein synthesis. J Biol Chem 284: 4968-77.
• Tamada, H., Thuan, N. V., Reed, P., Nelson, D., Katoku-Kikyo, N., Wudel, J., Wakayama, T. and Kikyo, N. (2006) Chromatin decondensation and nuclear reprogramming by nucleoplasmin. Mol Cell Biol 26: 1259-71.
• Gonda, K., Fowler, J., Katoku-Kikyo, N., Haroldson, J., Wudel, J., Kikyo, N. (2003)  Reversible disassembly of somatic nucleoli by the germ cell proteins FRGY2a and FRGY2b. Nature Cell Biol. 5: 205-10
• Kikyo, N., Wade, P. A., Guschin, D. and Wolffe, A. P. (2000) Active remodeling of somatic nuclei in egg cytoplasm by the nucleosomal ATPase ISWI. Science 289: 2360-2.
• Kikyo, N., and Wolffe, A. P. (2000) Reprogramming nuclei: insights from cloning, nuclear transfer and heterokaryons. J Cell Sci. 113: 11-20.