 |
The Journal of Neuroscience, February 18, 2004, 24(7):1680-1688; doi:10.1523/JNEUROSCI.3801-03.2004
Previous Article | Next Article 
Cellular/Molecular
Minimum Essential Factors Required for Vesicle Mobilization at Hippocampal Synapses
Marina G. Mozhayeva,1
Maria F. Matos,1
Xinran Liu,1,2 and
Ege T. Kavalali1,3
1Center for Basic Neuroscience, Departments of 2Molecular Genetics and 3Physiology, The University of Texas Southwestern Medical Center, Dallas, Texas 75390-9111
Studies on the mechanisms that underlie the function of small central presynaptic terminals have been hampered by the inaccessibility of these synapses to soluble reagents. Here, we permeabilized hippocampal synapses in culture, manipulated their interior, and monitored the resulting changes in vesicle mobilization with the styryl dye FM2-10. Using this method, we found that 1 µM Ca2+ after incubation with GTP or GTP- -S could mobilize 90% of the total recycling pool, whereas 1 µM Ca2+ application after dialysis of permeabilized synapses with GDP- -S mobilized 30% of the recycling vesicles, presumably corresponding to the readily releasable pool. In electron micrographs of permeabilized hippocampal synapses stimulated with 1 µM Ca2+, we could detect significant vesicle depletion after preincubation with GTP- -S, whereas preincubation with GDP- -S left the total vesicle pool relatively intact. Taken together, in this system replenishment of the readily releasable pool by the reserve vesicles was strictly GTP dependent. In contrast, vesicle replenishment and release did not require ATP or N-ethylmaleimide-sensitive factor (NSF); however, this process involved formation of new soluble NSF-attachment protein receptor (SNARE) complexes as judged by its sensitivity to tetanus toxin. These results suggest that in hippocampal synapses, vesicle mobilization and replenishment of the readily releasable pool require GTP and Ca2+ but do not necessitate ATP-dependent priming and SNARE recycling.
Key words: synaptic vesicle mobilization; synaptic vesicle recycling; cell permeabilization; SNARE; FM1-43; hippocampal culture
Received Aug 14, 2003;
revised January 10, 2004;
accepted January 10, 2004.
This article has been cited by other articles:

|
 |

|
 |
 
M. K. Klose, G. L. Boulianne, R. M. Robertson, and H. L. Atwood
Role of ATP-Dependent Calcium Regulation in Modulation of Drosophila Synaptic Thermotolerance
J Neurophysiol,
August 1, 2009;
102(2):
901 - 913.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. Talbot, J. N. Barrett, E. F. Barrett, and G. David
Stimulation-induced changes in NADH fluorescence and mitochondrial membrane potential in lizard motor nerve terminals
J. Physiol.,
March 15, 2007;
579(3):
783 - 798.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. Ertunc, Y. Sara, C. Chung, D. Atasoy, T. Virmani, and E. T. Kavalali
Fast Synaptic Vesicle Reuse Slows the Rate of Synaptic Depression in the CA1 Region of Hippocampus
J. Neurosci.,
January 10, 2007;
27(2):
341 - 354.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. J. Newton, T. Kirchhausen, and V. N. Murthy
Inhibition of dynamin completely blocks compensatory synaptic vesicle endocytosis
PNAS,
November 21, 2006;
103(47):
17955 - 17960.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
H. Tokuoka and Y. Goda
Myosin Light Chain Kinase Is Not a Regulator of Synaptic Vesicle Trafficking during Repetitive Exocytosis in Cultured Hippocampal Neurons.
J. Neurosci.,
November 8, 2006;
26(45):
11606 - 11614.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. N. Star, A. J. Newton, and V. N. Murthy
Real-time imaging of Rab3a and Rab5a reveals differential roles in presynaptic function
J. Physiol.,
November 15, 2005;
569(1):
103 - 117.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|

|