AUTHOR=Ávila-González Daniela , Portillo Wendy , García-López Guadalupe , Molina-Hernández Anayansi , Díaz-Martínez Néstor E. , Díaz Néstor F. TITLE=Unraveling the Spatiotemporal Human Pluripotency in Embryonic Development JOURNAL=Frontiers in Cell and Developmental Biology VOLUME=9 YEAR=2021 URL=https://www.frontiersin.org/journals/cell-and-developmental-biology/articles/10.3389/fcell.2021.676998 DOI=10.3389/fcell.2021.676998 ISSN=2296-634X ABSTRACT=

There have been significant advances in understanding human embryogenesis using human pluripotent stem cells (hPSCs) in conventional monolayer and 3D self-organized cultures. Thus, in vitro models have contributed to elucidate the molecular mechanisms for specification and differentiation during development. However, the molecular and functional spectrum of human pluripotency (i.e., intermediate states, pluripotency subtypes and regionalization) is still not fully understood. This review describes the mechanisms that establish and maintain pluripotency in human embryos and their differences with mouse embryos. Further, it describes a new pluripotent state representing a transition between naïve and primed pluripotency. This review also presents the data that divide pluripotency into substates expressing epiblast regionalization and amnion specification as well as primordial germ cells in primates. Finally, this work analyzes the amnion’s relevance as an “signaling center” for regionalization before the onset of gastrulation.