Bruchpilot, a Protein with Homology to ELKS/CAST, Is Required for Structural Integrity and Function of Synaptic Active Zones in Drosophila

• Published in: Neuron (Cambridge, Mass.) Mass.), 2006-03, Vol.49 (6), p.833-844
• Main Authors: Wagh, Dhananjay A., Rasse, Tobias M., Asan, Esther, Hofbauer, Alois, Schwenkert, Isabell, Dürrbeck, Heike, Buchner, Sigrid, Dabauvalle, Marie-Christine, Schmidt, Manuela, Qin, Gang, Wichmann, Carolin, Kittel, Robert, Sigrist, Stephan J., Buchner, Erich
• Format: Article
• Language: English
• Subjects: Adaptor Proteins, Signal Transducing - chemistry; Adaptor Proteins, Signal Transducing - metabolism; Animals; Animals, Genetically Modified; Behavior, Animal; Blotting, Northern - methods; Blotting, Western - methods; Brain research; CELLBIO; Cloning, Molecular; Drosophila; Drosophila Proteins - genetics; Drosophila Proteins - physiology; Dynamins - metabolism; Electrophoresis, Gel, Two-Dimensional - methods; Green Fluorescent Proteins - biosynthesis; Humans; Immunochemistry - methods; In Situ Hybridization - methods; Insects; Intracellular Signaling Peptides and Proteins - chemistry; Intracellular Signaling Peptides and Proteins - metabolism; Membrane Potentials - drug effects; Membrane Potentials - genetics; Membrane Potentials - physiology; Microscopy, Electron, Transmission - methods; Molecular Sequence Data; MOLNEURO; Nerve Tissue Proteins - chemistry; Nerve Tissue Proteins - metabolism; Neuromuscular Junction - physiology; Neuromuscular Junction - ultrastructure; Photoreceptors; Presynaptic Terminals - metabolism; PROTEINS; Reverse Transcriptase Polymerase Chain Reaction - methods; RNA, Messenger - biosynthesis; RNA, Small Interfering - pharmacology; Structural Homology, Protein; Walking - physiology
• ISSN: 0896-6273; 1097-4199
• DOI: 10.1016/j.neuron.2006.02.008

Neurotransmitters are released at presynaptic active zones (AZs). In the fly Drosophila, monoclonal antibody (MAB) nc82 specifically labels AZs. We employ nc82 to identify Bruchpilot protein (BRP) as a previously unknown AZ component. BRP shows homology to human AZ protein ELKS/CAST/ERC, which binds RIM1 in a complex with Bassoon and Munc13-1. The C terminus of BRP displays structural similarities to multifunctional cytoskeletal proteins. During development, transcription of the bruchpilot locus ( brp) coincides with neuronal differentiation. Panneural reduction of BRP expression by RNAi constructs permits a first functional characterization of this large AZ protein: larvae show reduced evoked but normal spontaneous transmission at neuromuscular junctions. In adults, we observe loss of T bars at active zones, absence of synaptic components in electroretinogram, locomotor inactivity, and unstable flight (hence “ bruchpilot”—crash pilot). We propose that BRP is critical for intact AZ structure and normal-evoked neurotransmitter release at chemical synapses of Drosophila.