The goal of this project was to develop a treatment for Angelman syndrome, a rare neurologic disease in which children have many physical and cognitive deficiencies, including lack of speech, difficulty or inability to walk, sleep disorders and seizures. We developed artificial gene regulatory proteins to turn on the protein that is missing the brains of these children. We used a type of adult stem cell call a mesenchymal stem cell to deliver the protein to the brain. The cells acted as protein factories, producing the gene regulatory protein directly in the brain where it was needed. We were able to show that the treatment was able to turn on the missing protein in the brains of a mouse model of Angelman syndrome. Further studies are needed to show if such a treatment can be safe and effective in people. The use of mesenchymal stem cells as a delivery system for similar types of gene regulatory proteins could represent an exciting new way to treat many other genetic diseases of the brain.