RT Journal Article
SR Electronic
T1 Immunoisolation of GABA-Specific Synaptic Vesicles Defines a Functionally Distinct Subset of Synaptic Vesicles
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 4904
OP 4911
DO 10.1523/JNEUROSCI.20-13-04904.2000
VO 20
IS 13
A1 Takamori, Shigeo
A1 Riedel, Dietmar
A1 Jahn, Reinhard
YR 2000
UL http://www.jneurosci.org/content/20/13/4904.abstract
AB Synaptic vesicles from mammalian brain are among the best characterized trafficking organelles. However, so far it has not been possible to characterize vesicle subpopulations that are specific for a given neurotransmitter. Taking advantage of the recent molecular characterization of vesicular neurotransmitter transporters, we have used an antibody specific for the vesicular GABA transporter (VGAT) to isolate GABA-specific synaptic vesicles. The isolated vesicles are of exceptional purity as judged by electron microscopy. Immunoblotting revealed that isolated vesicles contain most of the major synaptic vesicle proteins in addition to VGAT and are devoid of vesicular monoamine and acetylcholine transporters. The vesicles are 10-fold enriched in GABA uptake activity when compared with the starting vesicle fraction. Furthermore, glutamate uptake activity and glutamate-induced but not chloride-induced acidification are selectively lost during immunoisolation. We conclude that the population of GABA-containing synaptic vesicles is separable and distinct from vesicle populations transporting other neurotransmitters.