Professor Katsuhiko Hayashi is a globally renowned stem cell researcher who specializes in germline genetics at The University of Osaka.
Abstract
The germ cell lineage safeguards the integrity and diversity of genetic and epigenetic information through a unique series of differentiation processes, thereby ensuring the continuation of the species. To fully understand the mechanisms underpinning this continuity, many of which remain unclear, the reconstitution of the germ cell differentiation process in culture using pluripotent stem cells, known as in vitro gametogenesis, provides a powerful tool that facilitates both observation and perturbation.
Over the past decade, significant breakthroughs have been made in in vitro gametogenesis, consequently enabling the generation of functional germ cell lineages including primordial germ cells, oocytes, and spermatogenic cells, as well as reproductive somatic environments such as ovarian follicles and seminiferous tubules. These technical advances have been primarily established in murine models, but ongoing efforts are rapidly extending the approach to other mammalian species, including humans, livestock animals, and endangered species. Such progress not only enhances our understanding of species-specific aspects of reproduction but also holds promise for translational applications in reproductive medicine and conservation biology.
Concurrently, in vitro gametogenesis has begun to uncover molecular circuits and regulatory networks that underpin sex-specific germ cell differentiation and maintain genomic and epigenomic stability. These findings are shedding light on how germ cells counteract the accumulation of damage, transcriptional noise, and epigenetic drift that commonly affect somatic cells.
In this seminar, he will summarize recent advances in in vitro gametogenesis and highlight insights into the mechanisms that safeguard oocyte integrity during prolonged dormancy in the female germline.