Okadaic acid disrupts clusters of synaptic vesicles in frog motor nerve terminals

Okadaic acid disrupts clusters of synaptic vesicles in frog motor nerve terminals The fluorophore FM1-43 appears to stain membranes of recycled synaptic vesicles. We used FM1-43 to study mechanisms of synaptic vesicle clustering and mobilization in living frog motor nerve terminals. FM1-43 staining of these terminals produces a linear series of fluorescent spots, each spot marking the cluster of several hundred synaptic vesicles at an active zone. Most agents we tested did not affect staining, but the phosphatase inhibitor okadaic acid (OA) disrupted the fluorescent spots, causing dye to spread throughout the terminal. Consistent with this, electron microscopy showed that vesicle clusters were disrupted by OA treatment. However, dye did not spread passively to a uniform spatial distribution. Instead, time lapse movies showed clear evidence of active dye movements, as if synaptic vesicles were being swept along by an active translocation mechanism. Large dye accumulations sometimes occurred at sites of Schwann cell nuclei. These effects of OA were not significantly affected by pretreatment with colchicine or cytochalasin D. Electrophysiological recordings showed that OA treatment reduced the amount of acetylcholine released in response to nerve stimulation. The results suggest that an increased level of protein phosphorylation induced by OA treatment mobilizes synaptic vesicles and unmasks a powerful vesicle translocation mechanism, which may function normally to distribute synaptic vesicles between active zones. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The Journal of Cell Biology Rockefeller University Press

Okadaic acid disrupts clusters of synaptic vesicles in frog motor nerve terminals

The Journal of Cell Biology, Volume 124 (5): 843 – Mar 1, 1994

Loading next page...
 
/lp/rockefeller-university-press/okadaic-acid-disrupts-clusters-of-synaptic-vesicles-in-frog-motor-cw60Nxvq0Z
Publisher
Rockefeller University Press
Copyright
© 1994 Rockefeller University Press
ISSN
0021-9525
eISSN
1540-8140
D.O.I.
10.1083/jcb.124.5.843
Publisher site
See Article on Publisher Site

Abstract

The fluorophore FM1-43 appears to stain membranes of recycled synaptic vesicles. We used FM1-43 to study mechanisms of synaptic vesicle clustering and mobilization in living frog motor nerve terminals. FM1-43 staining of these terminals produces a linear series of fluorescent spots, each spot marking the cluster of several hundred synaptic vesicles at an active zone. Most agents we tested did not affect staining, but the phosphatase inhibitor okadaic acid (OA) disrupted the fluorescent spots, causing dye to spread throughout the terminal. Consistent with this, electron microscopy showed that vesicle clusters were disrupted by OA treatment. However, dye did not spread passively to a uniform spatial distribution. Instead, time lapse movies showed clear evidence of active dye movements, as if synaptic vesicles were being swept along by an active translocation mechanism. Large dye accumulations sometimes occurred at sites of Schwann cell nuclei. These effects of OA were not significantly affected by pretreatment with colchicine or cytochalasin D. Electrophysiological recordings showed that OA treatment reduced the amount of acetylcholine released in response to nerve stimulation. The results suggest that an increased level of protein phosphorylation induced by OA treatment mobilizes synaptic vesicles and unmasks a powerful vesicle translocation mechanism, which may function normally to distribute synaptic vesicles between active zones.

Journal

The Journal of Cell BiologyRockefeller University Press

Published: Mar 1, 1994

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Search

Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly

Organize

Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.

Access

Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve

Freelancer

DeepDyve

Pro

Price

FREE

$49/month
$360/year

Save searches from
Google Scholar,
PubMed

Create folders to
organize your research

Export folders, citations

Read DeepDyve articles

Abstract access only

Unlimited access to over
18 million full-text articles

Print

20 pages / month

PDF Discount

20% off