| 描述信息 |
Human gastrulation establishes the blueprint for three germ layers and the body axis in the early embryo. Concurrently, diverse extraembryonic cellular lineages are segregated to support proper gastrula development and pattern formation. The coordination of cellular patterning during this stage, along the anterior-posterior, left-right, and dorsal-ventral body axes, is regulated by dynamic signaling centers within the embryonic region and at the embryonic and extraembryonic interface. Comprehensive knowledge on the molecular code as well as the key events of embryonic and extraembryonic development in vivo, is crucial for comprehending human development and advancing stem-cell-based technologies. However, research on this stage is extremely challenging, particularly in humans, due to the inaccessibility and infrequent availability of in vivo embryos, as well as ethical concerns regarding in vitro cultured embryos. Here, we obtained a first in vivo intact gastrulating human embryo embryos corresponding to Carnegie stage eight (CS8), and performed serial transverse sectioning for single-cell stereo-seq, resulting in a comprehensive spatial transcriptomic dataset (totally 247,300 spots). Through virtual reconstruction of CS8 human embryo at single-cell resolution, we provide the first in vivo insights into the dynamic heterogeneity and developmental trajectories of the three germ layers with spatial diversity. Additionally, we systematically construct an atlas of the extraembryonic mesoderm and endoderm development. We traced the origin and maturation of hemogenic progenitors in the yolk sac and spatial pattern formation during morphogenesis. Finally, we perform cross-species comparisons of gastrulation among mice, monkeys, and humans. In summary, our data offers valuable insights into human gastrulation and its associated disorders. |
