Mutations of the PTEN gene cause neurons to grow to twice the size and form four times the number of synaptic connections to other neurons as a normal neuron. Removing the RAPTOR gene, an essential gene in the mTORC1 signaling pathway, prevents the neuronal and synaptic overgrowth associated with PTEN mutations. Using Rapamycin to inhibit mTORC1 recues all the changes in neuronal overgrowth.
