Related Experiment Video
Updated: Aug 16, 2026

Dissection and Imaging of Active Zones in the Drosophila Neuromuscular Junction
Published on: April 27, 2011
Endocytic active zones: hot spots for endocytosis in vertebrate neuromuscular terminals
H Teng1, J C Cole, R L Roberts
1Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Abstract:
We have used a sensitive activity-dependent probe, sulforhodamine 101 (SR101), to view endocytic events within snake motor nerve terminals. After very brief neural stimulation at reduced temperature, SR101 is visualized exclusively at punctate sites located just inside the presynaptic membrane of each terminal bouton. The number of sites (approximately 26 sites/bouton) and their location (in register with postsynaptic folds) are similar to the number and location of active zones in snake motor terminals, suggesting a spatial association between exocytosis and endocytosis under these stimulus conditions. With more prolonged stimulation, larger SR101-containing structures appear at the bouton margins. Thus endocytosis occurs initially at distinct sites, which we call "endocytic active zones," whereas further stimulation recruits a second endocytic paradigm.
More Related Videos
Related Concept Videos
Action Potentials
Muscle Contraction
Vesicular Tubular Clusters
With the help of motor proteins such...
Neuromuscular Junction And Blockade
The Neuromuscular Junction
Relaxation of Skeletal Muscles
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open.

