Cultured neurons from stage 11 embryos that express Efa6^UAS.EGFP under the control of Scer\GAL4^elav.PLu show a small but significant decrease in axon length and there is an increase in the number of cultured neurons without axons, compared to controls. Growth cones show increased microtubule polymerization, with fewer EB1 comets or microtubules in growth cone and fewer growth cone filopodia showing EB1 comets or microtubules, as compared to controls. The axon shalt does not show changes in growing microtubule number (i.e. EB1 comets), but there are fewer microtubules and growing microtubules in filopodia along the axon shaft. Expression under the control of either Scer\GAL4^elav.PLu or Scer\GAL4^sca.PU does not affect the organization of axonal microtubules.

The expression of Efa6^UAS.EGFP under the control of Scer\GAL4^ato.3.6 leads to a lower density of axonal branches both in cultured stage 11 embryonic neurons and in dorsal cluster neurons in the adult medulla, as compared to controls. In addition, unlike controls, dorsal cluster neuron axons are frequently absent from the medulla of young adults; this defect is not observed in older adults (15-days old).

Efa6^UAS.EGFP/Scer\GAL4^elav.PLu is a suppressor of axon microtubule bundle | embryonic stage phenotype of shot³