Shota Nakanoh, Ph.D. (Comparative Stem Cell Dynamics Lab, Babraham Institute, Cambridge, UK)

2023. 12. 21 (Thu) 10:00 ~ 11:00

1F Seminar Room 1, Myodaiji (132-134)

Division of Embryology Toshihiko Fujimori (5860)

Mechanisms specifying amniotic ectoderm and surface ectoderm are unresolved in human due to their close similarities in expression patterns and signal requirements. This lack of knowledge hinders the development of protocols to accurately model human embryogenesis. Here, we developed a human pluripotent stem cell model to investigate the divergence between amniotic and surface ectoderms. In the established culture system, cells differentiated to functional amnioblast-like cells. Single-cell RNA sequencing analyses of amnioblast differentiation revealed an intermediate cell state with enhanced surface ectoderm gene expression. Furthermore, when the differentiation started at confluent condition, cells retained the expression profile of surface ectoderm. Collectively, we propose that human amniotic ectoderm and surface ectoderm are specified along a common non-neural ectoderm trajectory based on cell density. Our culture system also generated extraembryonic mesoderm-like cells from the primed pluripotent state. Taken together, this study provides an integrative understanding of the human non-neural ectoderm development and a model for embryonic and extraembryonic human development around gastrulation.