Abstract
The bone morphogenetic proteins (BMPs) are secreted polypeptides of the TGF-beta family, whose diverse functions include primary neural induction and the dorsoventral patterning of the neural tube. In this issue of Neuron, Aberle et al. (2002) and Marqués et al. present evidence that BMP receptors may also influence the development of synapses. The results suggest a novel mechanism for regulating neuronal growth and synaptic homeostasis during development.