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Measuring Synaptic Vesicle Endocytosis in Cultured Hippocampal Neurons
Published on: September 4, 2017
The calcineurin-dynamin 1 complex as a calcium sensor for synaptic vesicle endocytosis
M M Lai1, J J Hong, A M Ruggiero
1Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
The Journal of Biological Chemistry
|September 3, 1999
Summary
Researchers discovered calcineurin and dynamin 1 form a calcium-dependent complex, acting as a calcium sensor to facilitate synaptic vesicle endocytosis.
Area of Science:
- Neuroscience
- Cell Biology
- Biochemistry
Background:
- Synaptic vesicle exocytosis is calcium-dependent, utilizing synaptotagmin as the calcium sensor.
- The calcium dependence of synaptic vesicle endocytosis has been proposed, but a specific sensor remained unidentified.
Purpose of the Study:
- To identify a calcium-sensing mechanism involved in synaptic vesicle endocytosis.
- To investigate the role of calcineurin and dynamin 1 in calcium-dependent endocytosis.
Main Methods:
- Investigated the physical association between calcineurin and dynamin 1.
- Quantified the calcium dependence of the calcineurin-dynamin 1 interaction using EC50 values.
- Assessed the impact of disrupting this interaction on clathrin-mediated endocytosis.
Main Results:
- A calcium-dependent physical association was identified between calcineurin and dynamin 1.
- The calcineurin-dynamin 1 interaction exhibits a calcium dependency with an EC50 between 0.1-0.4 microM.
- Disruption of the calcineurin-dynamin 1 complex formation inhibited clathrin-mediated endocytosis.
Conclusions:
- The calcium-dependent formation of the calcineurin-dynamin 1 complex serves as a novel calcium sensor for synaptic endocytosis.
- This complex, when localized with other endocytic proteins, facilitates the calcium-sensing process during synaptic vesicle recycling.
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