This manuscript presents a careful study of nervous system regeneration in the larval sea star using new transgenic tools for marking and following cells involved in regeneration. The authors find ...

Together with Hilde Mangold, he demonstrated that cells in the early stage of germ development in the gastrula are not yet defined for their later development. Spemann recognized that where they are ...

During animal ontogenesis, body axis patterning is finely regulated by complex interactions among several signaling pathways. Nitric oxide (NO) and retinoic acid (RA) are potent morphogens that play a ...