1981: Graduated, Faculty of Science, The University of Tokyo|
1986: Doctor of Science from The University of Tokyo
1986: Researcher, National Institute Health Japan
1989: Lecturer, Faculty of Science, The University of Tokyo
1992-1993: Researcher, Department of Zoology, University of Washington (Seattle, USA)
1995: Associate Professor, Graduate School of Science, The University of Tokyo
1999: Associate Professor, Graduate School of Frontier Sciences, The University of Tokyo
2005: Professor, Graduate School of Frontier Sciences, The University of Tokyo
|Graduate School: Molecular Mechanisms of Adaptation, Bioscience Analytical Instruments |
Others: Part-time Professor, University of the Air
|1) Molecular mechanism of retrotransposition of LINE and its application
LINE occupy over 20% of the human genome and cause many genetic diseases, but retrotransposition mechanisms remain to be elucidated. We have studied telomere-specific LINE in insects and recently established the retrotransposition system with baculovirus-mediated gene delivery. Using this system, we continue to clarify the essential domains for LINE retrotransposition and retrotoransposition mechanisms. We are also applying this system to sequence-specific gene delivery and gene therapy vectors. (Ref. 1)
2) Creation of enzymes specifically cutting telomeric repeats
Telomere-specific LINE encodes the endonuclease, which specifically cuts insect telomeric repeats (TTAGG)n. We found that the enzyme domain expressed in E. coli cuts not only (TTAGG)n but also the human (TTAGGG)n, which is the only enzyme known to specifically cut the telomeric repeats. The anti-telomerase reagent and telomere length regulation is thought to be a potent repressor for ageing and tumorigenesis. We are analyzing cutting mechanisms of the telomere cutting enzyme in LINE, and attempting to apply it to the anti-tumor reagent. (Ref. 2)
3) Regulation of wing morphogenesis by steroid hormone in insects
Metamorphosis which is an adaptive developmental process controlled by hormones is observed in a wide variety of animals. We have been studying wing morphogenesis in Lepidoptera and found that the steroid hormone, ecdysone, induces cell proliferation in distal wing regions and cell death in proximal wing regions. This event is controlled by region-specific expression of ecdysone receptor (EcR) isoforms. It is thought that insects lack sexual hormones, but vertebrates have them. Males of the tussock moth, Orgyia recens, have wings, while female moths lose their wings, which is difference that appears during metamorphosis. We found that ecdysone induces wing degeneration in a female-specific manner. Wing morphogenesis and sexual dimorphism in Lepidoptera are good models to study steroid action during metamorphosis. (Refs. 3, 4)
4) Molecular mechanisms of camouflage marking patterns in insects
Variation of marking patterns on the body surfaces of animals is developed during evolution and is useful for the lifestyle and behavior of each animal. In particular, marking patterns in insects are often used in mimicry and camouflage for protecting them from predators. We are studying the molecular mechanisms for larval body markings and wing patterns, using the silkworm mutant strains and swallowtail butterflies, which change their marking patterns during larval development.
1) Takahashi, H. et al. EMBO.J. 21, 408-417, 2002.
2) Anzai, T. et al. Mol.Cell.Biol. 21, 100-108, 2001.
3) Fujiwara, H. and Ogai, S. Dev. Genes. Evol. 211, 118-123, 2001
4) Lobbia, S. et al. J. Insect Sci. 3, 1-7, 2003.
|The Zoological Society of Japan|
The Molecular Biology Society of Japan
The Japanese Society of Sericultural Sciences
Society of Evolutionary Studies, Japan
The Genetic Society of Japan
International Ecdysone Workshop Organizing Committee
2006.6-2007.5 Member of Reviewing Committee Japan Prize 2007
|We would like to clarify the complete mechanisms of LINE retrotranspositions and apply its system to gene therapy vectors and anti-cancer reagents. For that purpose, collaborative research with other labs on campus and off-campus are necessary. In addition, we would like to study insect diversity and their ability to adapt systematically and to construct an academic field that has an impact on basic science. We also wish to contribute education in local communities in Kashiwa through our research on insect science.
|Messages to Students|
|On this campus, it is necessary to construct a system that stimulates and facilitates various research projects by collaboration both on-campus and off-campus and utilizes intellectual property. On the other hand, I am afraid that fundamental interest in nature is beginning to be lost from research. I hope that profitable research and non-profitable research can coexist in a balanced manner.|