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TheDrosophilaneuromuscular junction (NMJ) is an excellent model for studying vertebrate glutamatergic synapses. Researchers have uncovered fundamental mechanisms at the fly NMJ that are conserved in higher-order organisms. To gain molecular and structural insight into these and other structures, immunolabeling is invaluable. In this protocol, we describe how to use immunolabeling to visualize embryonic/larval presynaptic and postsynaptic structures at the NMJ. We also include details about amplification of weak immunohistochemistry signals and how to use these signals to quantify synaptic growth via bouton counting. Boutons are bead-like structures at motor axon terminals that house synapses, and the number of boutons reflects the size of the NMJ. We also describe how to identify the different bouton types.
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The Drosophila Larval Neuromuscular Junction: Developmental Overview
For decades, theDrosophilalarval neuromuscular junction (NMJ) has been a go-to model for synaptic development. This simple, accessible system is composed of a repeating pattern of 33 distinct neurons that stereotypically innervate 30 muscles. Fundamental mechanisms that underlie diverse aspects of axon pathfinding, synaptic form, and function have been uncovered at the NMJ, and new pathways continue to be uncovered. These discoveries are fueled by the ease of dissections and an extensive array of techniques. Chief among these techniques are various microscopy approaches, including super-resolution and electron microscopy. Functionally, theDrosophilaNMJ is glutamatergic, similar to the vertebrate central synapses, making it a great model to study normal development and neurological diseases. Here we provide a brief overview of the larval neuromuscular system, highlighting the connectivity patterns, development, and some of the mechanisms underlying these processes.
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- Award ID(s):
- 2048080
- PAR ID:
- 10564821
- Publisher / Repository:
- Cold Spring Harbor Laboratory Press
- Date Published:
- Journal Name:
- Cold Spring Harbor Protocols
- ISSN:
- 1940-3402
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1101/pdb.top108449
