11 Sep 1998

Neuronal growth and synapse formation is regulated by a combination of activity-independent and activity-dependent mechanisms. In today's Science, E. Nedivi et al. describe CPG15, a molecule that enhances dendritic arbor growth in projection neurons of Xenopus laevis, with no effect on interneurons. The molecule controls growth of neighboring neurons through an intercellular signaling mechanism that requires a glycosylphosphatidylinositol link. CPG15 may represent a new class of activity-regulated, membrane-bound, growth-promoting proteins that permit exquisite spatial and temporal control of neuronal structure.—June Kinoshita