Fas2EB112/Fas2e86 transheterozygotes do not have mushroom body lobe defects in the adult.
Dorsal longitudinal muscle a (DLMa) is innervated by a single motor neuron that has, on average, 5 contact points with the muscle in both wild type and Fas2e86 mutants.
Mutants exhibit a synaptic over-growth phenotype.
About 5% of mutant adult males show genitalia rotation defects.
The increase in frequency seen in the synaptic drive to aCC/RP2 during the first 28hr of larval life is not affected in the hypomorphic Fas2e86.
Mutants show overgrowth at the larval neuromuscular junction.
In 50% of the mushroom bodies of mutant animals, gross structural defects in the lobes and calyxes are seen.
50% increase in number of MN boutons at muscle 6. Mild heat induced expression of CrebB-17Aa.hs during larval stages significantly increases the quantal content of the synapse without altering quantal size (as shown by measuring excitatory postsynaptic potential, EPSP). Expression of CrebB-17Aa.hs increases the efficacy of single boutons in Fas2e86 to wild type.
In homozygous embryos the SNb fails to diverge from the ISN partially (partial bypass) in 6% segments. Fas2e93; beat-Ia2 flies have a strong beat-Ia phenotype, 86% segments have a divergence defect.
An increase in synaptic sprouting.
Growth of the synapse increases when Fas2 expression level is low causing a rise in number of boutons.
Neuronal activity is normal; bursting pattern of motor neuron action potentials controlling larval locomotion is similar to wild type. Excitatory postsynaptic potentials (EPSP) reveal synaptic transmission is also normal. Number of boutons is increased compared to wild type due to reduction in Fas2 expression, but the mean quantal content or the quantal size is not altered reflecting no change in synaptic strength. The extra boutons are not silent but should have an average quantal content lower than wild type. Bouton number does not increase when Fas2Scer\UAS.cLa is expressed from Scer\GAL4E62-2 in Fas2e86 larvae.