While studying abroad in the U.S., I happened to become involved in research concerning the development of reproductive cells. Since that time, I have been obsessed with and spent my life absorbed in the research of the wondrous properties of reproductive cells, which possess the ability to produce an entire individual organism.
Maeda, I., Okamura, D., Tokitake, Y., Ikeda, M, Kawaguchi, H., Mise, N., Abe, K., Noce, T., Okuda, A, Matsui, Y. Max is a repressor of germ-cell-related gene expression in mouse embryonic stem cells. Nature Communications 4, 1754 (2013).
Okamura, D., Maeda, I., Taniguchi, H., Tokitake, Y., Ikeda, M., Ozato, K., Mise, N., Abe, K., Noce, T., Izpisua Belmonte, J. C. and Matsui, Y. Cell-cycle gene-specific control of transcription has a critical role in proliferation of primordial germ cells. Genes & Development 26, 2477-2482 (2012).
Okamura, D., Mochizuki, K., Taniguchi, H., Tokitake, Y., Ikeda, M., Yamada, Y., Tournier, C., Yamaguchi, S., Tada, T., Scholer, H.R. and Matsui, Y. REST and its downstream molecule Mek5 regulate survival of primordial germ cells. Developmental Biology 372, 190-202 (2012).
Mochizuki, K., Tachibana, M., Saitou, M., Tokitake, Y., and Matsui, Y. Implication of DNA demethylation and bivalent histone modification for selective gene regulation in mouse primordial germ cells. PLoS ONE 7, e46036 (2012).
Matsui, Y., and Tokitake, Y. Primordial germ cells contain subpopulations that have greater ability to develop into pluripotential stem cells. Development Growth and Differentiation 51, 657-667 (2009).
Japanese Society of Developmental Biologists
Advanced Lecture on Mechanisms of Cellular Differentiation
Reproductive cells specialize from pluripotential stem cells into primordial germ cells during the initial stage of embryonic development and then further mature into sperm and eggs. Epigenetic control plays an important role in this process via the methylation of DNA and histones. What we have learned from our recent research is that the methylation of a particular histone serves to stop the specialization of pluripotential stem cells to germ cells. In addition, we have also found out that the demethylation of DNA and the methylation of histone combine, causing the expression of specific genes in response to the stage of germ cell differfentiation.
Although research is a fascinating job, good results rarely appear in line with what you expected. If things do not go well, you consider this and that, consult with the people around you, and occasionally spend days trying to solve the problem. When you finally solve the problem yourself, however, it is an extremely happy feeling, and if it leads to some new result, it is like reaching the limit of ecstasy. I would like to have many people participate in our research and experience the roller coaster-like excitement.