Erratum

These authors contributed equally to the work.

Present address: INSERM U583, Institut de Biologie, 4 Boulevard Henri IV, 34060 Montpellier, Cedex, France.

Present address: Department of Biosciences, Division of Animal Physiology, Biocenter 3 (Viikinkaari 1), P.O. Box 65, University of Helsinki, Finland.

Present address: AGY Therapeutics, Inc., 290 Utah Avenue, South San Francisco, California 94080.

Present address: Université de Bordeaux II, UMR.5091/Physiologie Cellulaire de la Synapse, Bordeaux 35077, France.

Present address: Novartis Pharma AG, Nervous System Research, CH-4002 Basel, Switzerland.

Present address: Laboratory for Neuronal Circuit Dynamics, Brain Science Institute, RIKEN, 2-1 Hirosawa, Wako-Shi, Saitama 351-0198, Japan.

Present address: Max-Planck Institut fur Experimentelle Medizin, Abt. Molekulare Neurbiologie, Hermann-Rein Strasse 3, D-37075, Gottingen, Germany.