During early embryonic development, cells have to make two things happen at the same time: they need to divide rapidly to increase the number of cells, while also changing their identity and organisation to build an embryo. One of the…
During early embryonic development, cells need to coordinate two fundamental processes: deciding what they will become and organising themselves into tissues. These processes have to happen in the right order and at the right time. But how does an embryo…
Embryonic development is usually a continuous process. After fertilisation, the embryo progresses through a series of developmental stages until it implants in the uterus and continues to grow. But in some mammals, embryos have evolved a remarkable ability to pause…
During early embryonic development, the cells that will eventually form the placenta undergo a remarkable transformation. A small population of cells at the embryonic pole of the blastocyst gives rise to the trophoblast stem-cell compartment, which subsequently expands and develops…
Early embryonic development is often described as a process in which cells progressively make increasingly irreversible decisions about their identity. But in the very early embryo, cells are remarkably flexible. They can adapt to changes in their environment, compensate for…
The early mouse embryo begins as a remarkably simple structure: a small group of pluripotent epiblast cells. Yet within a short period of time, these cells undergo a dramatic transformation. They change their developmental state, become polarised and reorganise into…
Pluripotency is usually thought of as a property of cell identity: pluripotent cells have the ability to give rise to many different cell types. But being pluripotent also means that a cell has to maintain a particular physical and metabolic…
Implantation is one of the most remarkable transitions in early pregnancy. The embryo has to attach to the uterus, invade the maternal tissue and establish connections with the mother’s blood supply. Yet many of the earliest events at this interface…
Early embryonic development requires a remarkable change in cellular activity. Before implantation, the mouse embryo is relatively metabolically quiet. After implantation, this changes dramatically: the epiblast begins to proliferate rapidly, reorganises into an epithelial structure and undergoes the morphogenetic transformations…
How does a simple ball of cells transform into an organised embryo? Around the time of implantation, the mouse embryo undergoes one of the most dramatic transformations in early development. The blastocyst, which contains a hollow cavity surrounded by several…