Disruption of these proteins can silence neurons by preventing the release of neurotransmitter-containing vesicles. Expression of the light chain of tetanus toxin (UAS-TNT or Tet or TeTxLc) cleaves nSyb and blocks vesicle release ( Sweeney et al., 1995). Cell Cycle inhibitor UAS-TNT has been used to study the role of transmitter release in axon guidance and synapse formation ( Tripodi et al., 2008) as well as to determine the role of many types of neurons in different behaviors ( Kong et al., 2010b) although some neurons seem to be less susceptible to TNT ( Thum et al., 2006). UAS-TNT was originally tested in glutamatergic motor neurons; the release machinery for biogenic amines,

including serotonin, dopamine, octopamine, tyramine, and neuropeptides may differ. Some aminergic neurons do show phenotypes with UAS-TNT ( Friggi-Grelin et al., 2003). UAS-TNT can also affect peptide release of the Eclosion Hormone releasing cells ( McNabb and Truman, 2008), but it may not be fully effective on Pigment Dispersment Factor ( Kaneko and Hall, 2000, Blanchardon et al., 2001 and Umezaki et al., 2011) or Crustacean Cardiac Activating Peptide release ( Luan et al., 2006a). A UAS-FRT-stop-FRT-TNT is available for

intersectional experiments ( Keller et al., 2002). UAS-TNT has major virtues: it targets a neural-specific protein, and thus should only block vesicle release in neurons. Moreover, as it is a potent toxin, even low levels of expression are effective. Since Fossariinae UAS-TNT is constitutively active, chronic expression may lead to some circuit-level this website form of compensation for the silenced neurons, or cell damage within them. A way to silence neurons acutely can bypass developmental roles, reduce pleiotropic effects, and minimize the opportunity for compensation. UAS-Shibirets1, a temperature-sensitive dominant-negative form of dynamin, a GTPase required for vesicle recycling,

blocks chemical neurotransmission acutely (Kitamoto, 2001). Although UAS-Shibirets1 affects vesicle recycling in many cell types, it may act most quickly in neurons where vesicle recycling is a rate-limiting step for neurotransmission. UAS-Shibirets1 is effective in many different neuronal types, including photoreceptors and cholinergic neurons (Kitamoto, 2001), as well as peptidergic and aminergic neurons (Krashes et al., 2009 and Alekseyenko et al., 2010). UAS-Shibirets1 has been used to identify neurons involved in courtship, sleep, color vision, and taste discrimination (Kitamoto, 2002, Broughton et al., 2004, Pitman et al., 2006, Gao et al., 2008b and Masek and Scott, 2010). The acute temporal control afforded by UAS-Shibirets1 allows investigation of neurons in adult behavior and even discrimination between neurons involved in learning and memory retrieval (Waddell et al., 2000, Dubnau et al., 2001, McGuire et al., 2001 and Kasuya et al., 2009).