Deciphering the role of the core pluripotency transcription factors Oct4 and Sox2 in the tissue-scale organisation of the embryonic lineage

• Applicant: Dr. Ivan Bedzhov
• Subject Area: Developmental Biology ; Reproductive Medicine, Urology ; Cell Biology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 546036305

The fertilised egg forms a multicellular embryo that gradually adopts various shapes as embryogenesis progresses from the pre- to post-implantation stages of development. As shape and function are intrinsically interconnected, the dynamic changes in the tissue architecture and the cell fate transitions of the early lineages have to be tightly coordinated. At the cellular level, a major driver of embryonic morphogenesis is the establishment of epithelial polarity, which takes place at precise developmental time points. The extraembryonic tissues are the first to adopt epithelial morphology during the preimplantation stages followed by the pluripotent cells of the epiblast immediately after implantation. We found that the developmental timing of the epiblast polarisation is controlled by the molecular cooperativity of the core pluripotency transcription factors Oct4 and Sox2. Our preliminary results indicate that the pluripotent cells are actively maintained in an apolar state, allowing proper tissue segregation of the epiblast and the primitive endoderm. Here we aim to decipher the cellular mechanisms and the developmental significance of this process.

• DFG Programme: Research Grants