Inhibition of neurotransmitter release in the lamprey reticulospinal synapse by antibody-mediated disruption of SNAP-25 function. / Löw, Peter; Norlin, Thomas; Risinger, Carl; Larhammar, Dan; Pieribone, Vincent A.; Shupliakov, Oleg; Brodin, Lennart.
In: European Journal of Cell Biology, Vol. 78, No. 11, 01.01.1999, p. 787-793.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - Inhibition of neurotransmitter release in the lamprey reticulospinal synapse by antibody-mediated disruption of SNAP-25 function
AU - Löw, Peter
AU - Norlin, Thomas
AU - Risinger, Carl
AU - Larhammar, Dan
AU - Pieribone, Vincent A.
AU - Shupliakov, Oleg
AU - Brodin, Lennart
PY - 1999/1/1
Y1 - 1999/1/1
N2 - The lamprey giant reticulospinal synapse can be used to manipulate the molecular machinery of synaptic vesicle exocytosis by presynaptic microinjection. Here we test the effect of disrupting the function of the SNARE protein SNAP-25. Polyclonal SNAP-25 antibodies were shown in an in vitro assay to inhibit the binding between syntaxin and SNAP-25. When microinjected presynaptically, these antibodies produced a potent inhibition of the synaptic response. Ba2+ spikes recorded in the presynaptic axon were not altered, indicating that the effect was not due to a reduced presynaptic Ca2+ entry. Electron microscopic analysis showed that synaptic vesicle clusters had a similar organization in synapses of antibody-injected axons as in control axons, and the number of synaptic vesicles in apparent contact with the presynaptic plasma membrane was also similar. Clathrin-coated pits, which normally occur at the plasma membrane around stimulated synapses, were not detected after injection of SNAP-25 antibodies, consistent with a blockade of vesicle cycling. Thus, SNAP-25 antibodies, which disrupt the interaction with syntaxin, inhibit neurotransmitter release without affecting the number of synaptic vesicles at the plasma membrane. These results provide further support to the view that the formation of SNARE complexes is critical for membrane fusion, but not for the targeting of synaptic vesicles to the presynaptic membrane.
AB - The lamprey giant reticulospinal synapse can be used to manipulate the molecular machinery of synaptic vesicle exocytosis by presynaptic microinjection. Here we test the effect of disrupting the function of the SNARE protein SNAP-25. Polyclonal SNAP-25 antibodies were shown in an in vitro assay to inhibit the binding between syntaxin and SNAP-25. When microinjected presynaptically, these antibodies produced a potent inhibition of the synaptic response. Ba2+ spikes recorded in the presynaptic axon were not altered, indicating that the effect was not due to a reduced presynaptic Ca2+ entry. Electron microscopic analysis showed that synaptic vesicle clusters had a similar organization in synapses of antibody-injected axons as in control axons, and the number of synaptic vesicles in apparent contact with the presynaptic plasma membrane was also similar. Clathrin-coated pits, which normally occur at the plasma membrane around stimulated synapses, were not detected after injection of SNAP-25 antibodies, consistent with a blockade of vesicle cycling. Thus, SNAP-25 antibodies, which disrupt the interaction with syntaxin, inhibit neurotransmitter release without affecting the number of synaptic vesicles at the plasma membrane. These results provide further support to the view that the formation of SNARE complexes is critical for membrane fusion, but not for the targeting of synaptic vesicles to the presynaptic membrane.
KW - Exocytosis
KW - SNARE
KW - Synaptic vesicle
KW - Synaptobrevin
KW - Syntaxin
UR - http://www.scopus.com/inward/record.url?scp=0344577857&partnerID=8YFLogxK
U2 - 10.1016/S0171-9335(99)80029-6
DO - 10.1016/S0171-9335(99)80029-6
M3 - Article
C2 - 10604655
AN - SCOPUS:0344577857
VL - 78
SP - 787
EP - 793
JO - European Journal of Cell Biology
JF - European Journal of Cell Biology
SN - 0171-9335
IS - 11
ER -
ID: 40834891