Primate gastrulation and early organogenesis at single-cell resolution

Our understanding of human early development is severely hampered by limited access to embryonic tissues. Due to their close evolutionary relationship with humans, non-human primates (NHPs) are often used as surrogates to understand human development but currently suffer from a lack of in vivo datasets, especially from gastrulation to early organogenesis during which the major embryonic cell types are dynamically specified. To fill this gap, we have collected six Carnegie stage (CS) 8-CS11 cynomolgus monkey embryos and performed in-depth transcriptome analyses of 56,636 single cells. Our analyses reveal transcriptomic features of major peri-gastrulation cell types, which help shed light on morphogenetic events including primitive streak (PS) development, somitogenesis, gut tube formation, neural tube patterning, and neural crest regionalization in primates. In addition, comparative analyses with mouse embryos and human embryoids uncover conserved and divergent features of peri-gastrulation development across species, e.g. species-specific dependency on Hippo signaling during presomitic mesoderm differentiation, and provide an initial assessment of relevant stem cell models of human early organogenesis. This comprehensive single-cell transcriptome atlas not only fills the knowledge gap in the NHP research field but also serves as an invaluable resource for understanding human embryogenesis and developmental disorders. single cells from cynomolgus monkey embryo tissues spanning different developmental stages during early pregnancy were used to do single-cell RNA-Seq experiments