Monitoring Rapid Endocytosis in the Electron Microscope via Photoconversion of Vesicles Fluorescently Labeled with FM1-43

  • Thomas Schikorski
Part of the Methods in Molecular Biology book series (MIMB, volume 657)


Cells communicate via endo- and exocytosis with their environment and neighboring cells. At synapses of the nervous system, fast exocytosis is coupled to fast endocytosis, which forms the basis for neurotransmitter release. The introduction of the unique fluorescent FM dyes allowed the monitoring of fast synaptic vesicle exo-endocytic cycling during live imaging sessions and after photoconversion of FM dyes into an electron-dense diaminobenzidine polymer synaptic vesicle cycling can be studied in the electron microscope. This protocol describes FM dye labeling of synaptic vesicles of cultured hippocampal neurons and photoconversion of the fluorescent synaptic vesicles for analysis in the electron microscope (EM).

Key words

Membrane retrieval activity-dependent labeling of synaptic vesicles hippocampal cell culture 


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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Thomas Schikorski
    • 1
  1. 1.Neuroscience DepartmentUniversidad Central del CaribeBayamonUSA

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