[1] RIKEN, Brain Sci Inst, Lab Cell Recovery Mech, Wako, Saitama 3510198, Japan
[2] Osaka Univ, Grad Sch Med, Dept Neurosci, Div Neuroanat, Suita, Osaka 5650871, Japan
[3] CREST, Suita, Osaka 5650871, Japan
[4] Harvard Univ, Sch Med, Dept Cell Biol, Boston, MA 02115 USA
[5] Natl Inst Neurosci, Div Dev & Differentiat, Tokyo 1878502, Japan