Developmental tumours, early differentiation and the transforming growth factor beta superfamily

Embryonal carcinoma and embryonic stem cells have been very useful models for identifying some of the factors that regulate differentiation in early mammalian development. Here, we present a brief history of their original isolation and characterization and of their later introduction into the Hubrecht Laboratory. We illustrate in a review their contribution to our current understanding of the function of transforming growth factor beta and ligands binding to the receptors of a related factor, activin, in development with some of our own work.