In a study published in the journal Nature, researchers looked at the biological pathways active in human embryos during their first few days of development to understand how cells acquire different fates and functions within the early embryo.
They observed that shortly after fertilisation as cells start to divide, some cells start to stick together. This triggers a cascade of molecular events that initiate placental development. A subset of cells change shape, or ‘polarise’, and this drives the change into a placental progenitor cell — the precursor to a specialised placenta cell — that can be distinguished by differences in genes and proteins from other cells in the embryo.
