unc-13^EMS7.5/unc-13^P84200 transheterozygotes that also express unc-13^{GoF.UAS.A.GFP} under the control of Scer\GAL4^RapGAP1-OK6 show neurotransmission defects in the second/third instar larval muscle 6 NMJ: increased evoked release amplitude; increase in frequency but decrease in amplitude of spontaneous release events.

unc-13^P84200/+ flies are significantly more resistant to the sedative (loss of righting reflex) effects of ethanol than controls, with no difference in ethanol absorption or metabolism.

unc-13^P84200/unc-13^EMS7.5 and unc-13^P84200/unc-13^EMS7.96 transheterozygotes are nearly lethal, as they give rise to few larvae, which hardly move and only occasionally develop into weak adult flies. unc-13^P84200 homozygotes bearing unc-13^Bnull are viable and fertile.

The third instar larval neuromuscular junction of unc-13^P84200/unc-13^EMS7.5 transheterozygotes exhibit a significant decrease in active zone density (identified by Bruchpilot puncta), which are often larger and exhibit apparently larger T-bars and a decrease in the number of synaptic vesicles docked in close proximity to the T-bar center, as compared to controls; neurotransmission at these neuromuscular junctions exhibits a severe decrease in the amplitude and a significant increase in the rise time of evoked excitatory currents, and significant increases in the amplitude and the frequency, but not in the rise time or decay time, of miniature excitatory currents, as compared to controls.

The third instar larval neuromuscular junction of unc-13^P84200 homozygotes bearing unc-13^Bnull exhibit a significant decrease in active zone (identified by Bruchpilot puncta) density, but not size, as compared to controls; neurotransmission at these neuromuscular junctions exhibit a significant decrease in the amplitude, but not kinetics, of evoked excitatory currents, and a significant increase in decay time, but not in amplitude or frequency, of miniature excitatory currents, as compared to controls.

unc-13^P84200 heterozygotes exhibit 50% wild-type levels of unc-13 mRNA and display a very robust increase in ethanol self-administration. These heterozygotes consume slightly less liquid food overall, compared with wild-type flies. This increased preference for ethanol is not because of a change in naive gustatory salience as both the food and the food plus ethanol elicit the same proboscis extension reflex in unc-13^P84200 heterozygotes.

Gross morphology of homozygous embryos is normal. Neuronal processes, cell bodies and synapses, boutons and synaptic vesicle markers are all morphologically normal. High frequency stimulation of mutant embryo motor nerves elicits only limited neurotransmission. Amplitude of rare mEJCs is normal. Average EJC amplitude unchanged at 5, 10 and 20 Hz stimulation. Increase in extracellular calcium does not significiantly improve transmission efficacy. Synaptic terminals lack stimulus-induced vesicle fusion. Response to hyperosmotic saline is severly reduced. Ultrastructural analysis reveals a 50% increase in number of synaptic vesicles per bouton, with a 50% increase in docked vesicles also, suggesting failure of synaptic vesicle exocytosis.

unc-13^P84200 has chemical resistant | adult stage phenotype, suppressible | partially by Rnor\Unc13a^UAS.cXa.EGFP/Scer\GAL4^elav.PLu

unc-13^P84200 has abnormal locomotor behavior | adult stage | chemical conditional phenotype, suppressible | partially by Rnor\Unc13a^UAS.cXa.EGFP/Scer\GAL4^elav.PLu

unc-13^P84200 has lethal - all die before end of P-stage | recessive phenotype, non-suppressible by Rnor\Unc13a^UAS.cXa.EGFP/Scer\GAL4^elav.PLu

unc-13^P84200 has lethal - all die before end of P-stage | recessive phenotype, non-suppressible by Scer\GAL4^nSyb.PU/Rnor\Unc13a^UAS.cXa.EGFP

unc-13^P84200 has lethal - all die before end of P-stage | recessive phenotype, non-suppressible by Rnor\Unc13a^UAS.cXa.EGFP/Scer\GAL4^Tub.PU