1. Department of Neurosciences and Division of Biology, Section of Neurobiology, University of California, San Diego, La Jolla, CA 92093, USA.
2. Department of Pharmacology, University of California, San Diego, La Jolla, CA 92093, USA.
3. Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA.
4. Genetics and Aging Research Unit, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA.
5. Department of Neuroscience, N. Bud Grossman Center for Memory Research and Care, and Institute for Translational Neuroscience, University of Minnesota, Minneapolis, MN 55414, USA.
6. Biotechnology Centre of Oslo, University of Oslo, Oslo 0317, Norway.