Human embryo polarization requires PLC signaling to mediate trophectoderm specification

• DOI: 10.7554/elife.65068
• Publication Date: 2021-09-27T12:13:41Z
• Authors: Meng Zhu; Marta Shahbazi; Angel Martin; Chuanxin Zhang; Berna Sozen; Mate Borsos; Rachel S Mandelbaum; Richard J Paulson; Matteo A Mole; Marga Esbert; Shiny Titus; Richard T Scott; Alison Campbell; Simon Fishel; Viviana Gradinaru; Han Zhao; Keliang Wu; Zi-Jiang Chen; Emre Seli; Maria J de los Sa...; Magdalena Zernick...
• Keywords: 0301 basic medicine; Time Factors; 590; Phospholipase C beta; Embryo Culture Techniques; Phosphoinositide Phospholipase C; Pregnancy; cell biology; Biology (General); pre-implantation; cell fate; 0303 health sciences; Q; R; Cell Polarity; Gene Expression Regulation, Developmental; Cell Differentiation; human embryo; cell polarity; Cell polarity; Medicine; Female; Research Article; Signal Transduction; Adult; 570; Cell biology; QH301-705.5; Science; GATA3 Transcription Factor; Gene Expression Regulation, Enzymologic; QH301; developmental biology; Young Adult; 03 medical and health sciences; Human embryo; Humans; Cell Lineage; Preimplantation; Body Patterning; polarization; preimplantation; Cell Biology; Embryo, Mammalian; Actins; QR; Other; Developmental Biology

Apico-basal polarization of cells within the embryo is critical for segregation distinct lineages during mammalian development. Polarized become trophectoderm (TE), which forms placenta, and apolar inner cell mass (ICM), founding population fetus. The cellular molecular mechanisms leading to human its timing embryogenesis have remained unknown. Here, we show that occurs in two steps: it begins with apical enrichment F-actin followed by accumulation PAR complex. This two-step process leads formation an domain at 8-16 stage. Using RNA interference, requires Phospholipase C (PLC) signaling, specifically enzymes PLCB1 PLCE1, from eight-cell stage onwards. Finally, although expression TE differentiation marker GATA3 can be initiated independently polarization, downregulation PLCE1 decreases through a reduction number polarized cells. Therefore, reinforces fate. results present here demonstrate how triggered regulate first lineage embryos.