Gene expression dynamics underlying cell fate emergence in 2D micropatterned human embryonic stem cell gastruloids

Human embryonic stem cells cultured in 2D micropatterns with BMP4 differentiate into a radial arrangement of germ layers and extra-embryonic cells. Single-cell transcriptomes demonstrate generation of cell types transcriptionally similar to their in vivo counterparts in Carnegie stage 7 human gastrula. Time-course analyses indicate sequential differentiation, where the epiblast arises by 12 h between the prospective ectoderm in the center and the cells initiating differentiation toward extraembryonic fates at the edge. Extraembryonic and mesendoderm precursors arise from the epiblast by 24 h, while nascent mesoderm, endoderm, and primordial germ cell-like cells form by 44 h. Dynamic changes in transcripts encoding signaling components support a BMP, WNT, and Nodal hierarchy underlying germ-layer specification conserved across mammals, and FGF and HIPPO pathways being active throughout differentiation. This work also provides a resource for mining genes and pathways expressed in a stereotyped 2D gastruloid model, common with other species or unique to hu-man gastrulation.

Automated summary

Human embryonic stem cells cultured in 2D micropatterns with BMP4 differentiate into radial arrangement of germ layers and extra-embryonic cells, generating cell types transcriptionally similar to in vivo counterparts. Time-course analyses show sequential differentiation, with signaling components supporting germ-layer specification conserved across mammals. This study provides a resource for mining genes and pathways expressed in a stereotyped 2D gastruloid model, common with other species or unique to human gastrulation.