Vesicular Glutamate Transporter--Shooting Blanks

Brain activity depends on the release of the neurotransmitter glutamate by exocytosis of synaptic vesicles. In their Perspective, Schuske and Jorgensen comment on two studies ( Fremeau et al ., Wocjik et al .) that find that mice with the main vesicular glutamate transporter knocked out survive for several months. However, the two studies present different models for subcellular localization of the vesicular transporter and for vesicle loading.