Life and Death in the Developing Spinal Cord

Abstract

The developing spinal cord follows morphogenic gradients that emanate from the floor plate and notochord. One of the signals is Sonic hedgehog (Shh). Shh does more than direct morphogenesis because it is also required for survival of the neuroepithelium. Thibert et al. (see the Perspective by Guerrero and Ruiz i Altaba) show that the receptor for Shh, known as Patched, stimulates apoptotic cell death in the absence of Shh. Thus, refinement of spinal cord architecture results from a balance of morphogenic and apoptotic signals negotiated through signaling by Shh and its receptor Patched. C. Thibert, M.-A. Teillet, F. Lapointe, L. Mazelin, N. M. Le Douarin, P. Mehlen, Inhibition of neuroepithelial Patched-induced apoptosis by Sonic hedgehog. Science 301, 843-846 (2003). [Abstract] [Full Text] I. Guerrero, A. Ruiz i Altaba, Longing for ligand: Hedgehog, patched, and cell death. Science 301, 774-776 (2003) [Summary] [Full Text]