1. Department of Molecular and Medical Pharmacology, University of California Los Angeles (UCLA), Los Angeles, CA 90095, USA.
2. Department of Psychiatry and Biobehavioral Sciences, Intellectual Development and Disabilities Research Center at Semel Institute for Neuroscience, UCLA, Los Angeles, CA 90095, USA.
3. Molecular Biology Institute, UCLA School of Medicine, Los Angeles, CA 90095, USA.
4. Laboratory of Regulation of Neuronal Development, Institute for Protein Research, Osaka University, Suita, Osaka, 565-0871, Japan.
5. Novartis Institutes for Biomedical Research, Cambridge, MA 02139, USA.
6. Howard Hughes Medical Institute, Department of Biochemistry and Biophysics, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.