EIF3D Safeguards the Homeostasis of Key Signaling Pathways in Human Primed Pluripotency [RNA-Seq]

Pluripotent stem cell identities such as differentiation and infinite proliferation have long been decoded in the frameworks of transcription factor networks, epigenomes, and signal transduction, yet unclear and fragmented. However, directing attention toward translation regulation, the bridge between these events promises to provide new insights into previously unexplained mechanisms. Functional screening led to the discovery that EIF3D maintains primed pluripotency via selective translation regulation. The loss of EIF3D unbalanced the pluripotency-associated signaling pathways, disrupting primed pluripotency. Furthermore, we found that EIF3D safeguards robust proliferation by managing the translation of multiple p53 regulators that maintain low p53 activity in the undifferentiated state. Therefore, this study provides a paradigm for selective translation regulation that defines the primed pluripotent stem cell identity. Overall design: To investigate the effect of EIF3D knockdown, we established cell line for EIF3D knockdown by using CRISPRi system which Cas proteins were induced by with doxycycline (DOX) treatment. iPSCs with non-targeting guide RNAs were used as control. RNA-seq data were obtained from 0, 3, 5 days after DOX treatment. To compare with loss of pluripotency states, POU5F1, SOX2 and NANOG knockdown lines were also established and sampled, in addition to endoderm, mesoderm and ectoderm like cells derived from iPSCs. To induce changes observed in EIF3D knockdown PSCs, we employed the chemical compounds and growth factor to including the activation of EGF/MAPK, mTOR, AKT, WNT, and p53, and inhibition of TGFß.