Abstract

The reconstitution in vitro of gametogenesis using pluripotent stem cells, which eventually produces functional gametes, has long been sought in reproductive biology and developmental biology. This process, known as in vitro gametogenesis, would not only enhance our understanding of the mechanisms underlying germ cell development but also provide an alternative source of gametes for reproduction. Since functional primordial germ cells were reconstituted from mouse pluripotent stem cells, in vitro gametogenesis has been extended to various mammalian species, including humans, livestock animals, and endangered animals. We developed culture systems that induce primordial germ cells from pluripotent stem cells of various mammalian species. In parallel, we have been working on the reconstitution of gonadal somatic cells, which support the maturation of stem cell-derived germ cells in culture. In this seminar, I will provide an overview of in vitro gametogenesis, discuss recent advancements in our research, and present new insights into the mechanisms of germ cell development, with a focus on oocyte formation. 

Biography

Katsuhiko Hayashi (born Dec. 2, 1971) is a full professor in the Department of Genome Biology at the Graduate School of Medicine, Osaka University, specializing in germ cell development and in vitro reconstitution. His career includes an MS from Meiji University (1994-1996); assistant professor at Tokyo University of Science (1996-2002); staff researcher at Osaka Medical Center (Ph.D., 2004); postdoctoral fellow at the Gurdon Institute, University of Cambridge (2005-2009); associate professor at Kyoto University (2009-2014); and full professor at Kyushu University (2014-2021). Since 2021, he has held his current position at Osaka University. Hayashi’s group aims to elucidate the genetic and epigenetic regulation of mammalian oocyte differentiation, employing a unique culture system to generate oocytes from pluripotent stem cells.