Neurofibromin signaling and synapses.

Neurofibromin, encoded by the Neurofibromatosis type I (NF1) gene, has been shown to regulate the Ras and cAMP signaling pathways. The signaling functions of neurofibromin may account for tumor formation in patients with NF1, as well as influencing neuronal function. Learning defects have been documented in NF1 mutant mice, and in NF1 patients, learning disabilities are common. In this review, the recent studies related to the role of neurofibromin in neuronal morphogenesis will be discussed, which may partly explain why the patients with NF1 have learning defects.