Expressing pdm3UAS.long under the control of Scer\GAL4GMR22C07 in combination with Scer\GAL80[tsh-GAL80] (to inhibit expression in thoracic segments) induces axon misrouting in vtd2 neurons of abdominal segments 4-6 in third instar larvae. Unlike wild-type controls which innervate the ventral nerve cord, misexpressing vtd2 neurons project into the subesophageal ganglion (SEG), establishing presynaptic brp-positive sites along the way. Their significantly elongated axon is similar in length to wild-type pdm3-positive SEG-targeting vtd1 neurons of abdominal segments 4-6.
Expressing pdm3UAS.long under the control of Scer\GAL4ppk.PG induces axon targeting defects in class IV da neurons: defasciculation, axon wandering away from the ventral neuropil, and thinning of the axon scaffold near the midline. Some stray class IV da axons project anteriorly towards the SEG.