This research project aims to implement a new innovative therapeutic approach based on messenger RNA (mRNA) to treat Neurofibromatosis type I. This genetic disease is caused by mutations (more than 1,900 mutations listed) in the NF1 gene. It affects one in 3,000 individuals and manifests itself in the appearance of multiple symptoms. The most common (99 % of patients are affected) is the development of painful, disfigured benign tumors located in the nerve endings of the skin. These tumors called skin neurofibromas (CNF) appear at puberty and their number increases throughout life up to thousands. Plexiform neurofibromas (pNFs) that affect 30 % of patients, appear in childhood and can degenerate into highly aggressive nerve sheath cancer (MPNST). Other symptoms include hyperpigmentation of the skin, eye or bone damage, and deficits in attention and learning. Our project is focused on CNFs, present in a vast majority of patients. The protein encoded by the NF1 gene mutated in disease (Nf1 or neurofibromine) is a multifunctional protein. The best described of its functions is its GAP (GTPase-activating protein) activity on Ras which allows the negative regulation of several signaling pathways involved in cell proliferation (MAPK and PI3K/mTor pathways). However, Nf1 exercises other fo...