A team of developmental biologists at the University of Massachusetts Amherst led by Dominique Alfandari, with others at MIT, report in a new paper that they have for the first time described how two transcription factors that are “absolutely essential for human development” are regulated by a cell surface metalloprotease known as ADAM13. The discovery adds to knowledge of how cells migrate in vertebrate embryos, how stem cells differentiate and how cancer cells metastasize.