Vesicular Monogamy?

Department of Psychiatry and Biobehavioral Sciences, Hatos Center for Neuropharmacology, The David Geffen School of Medicine, University of California, Los Angeles, California 90095, USA.
Neuron (Impact Factor: 15.05). 02/2006; 49(1):1-2. DOI: 10.1016/j.neuron.2005.12.013
Source: PubMed


Some 50 years ago, Bernard Katz and colleagues demonstrated that neurotransmitter is released as packets, or quanta, and a wealth of subsequent data have shown that synaptic vesicles (SVs) are the physical correlate of these quanta (Atwood and Karunanithi, 2002). Vesicular neurotransmitter transporters are responsible for packaging neurotransmitter into the lumen of the vesicle and thereby generating the concentration and absolute quantity of transmitter that makes up each quanta (see Hediger et al., 2004 and accompanying articles). But how much neurotransmitter is contained in the lumen of each vesicle? Is that number absolutely fixed, or might it vary depending on the activity of the transporter and the number of transporters that localize to each vesicle? And finally, how many transporters are required to localize to an individual SV in order to fill the lumen of the vesicle? The molecular-genetic analysis of vesicular transporters has begun to yield answers to some of these questions (Colliver et al., 2000, Fremeau et al., 2004, Pothos et al., 2000, Wilson et al., 2005 and Wojcik et al., 2004), and in this issue of Neuron, a paper from the DiAntonio lab suggests that the number of transporters required to fill a vesicle may be as few as one (Daniels et al., 2006).

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