The third instar larval stage is extended substantially in animals expressing mtTFB2^Scer\UAS.cAa under the control of Scer\GAL4^da.G32 compared to controls, with most of the larvae living more than 30 days after egg laying. The larvae remain close to the food without entering the wandering phase and never embark upon pupariation. The mutant larvae show a significant reduction in their length and diameter compared to control larvae.

The brains of larvae expressing mtTFB2^Scer\UAS.cAa under the control of Scer\GAL4^da.G32 are significantly smaller than normal, and they show decreased incorporation of BrdU in the optic lobes compared to controls. There is a severe reduction in the number of cells in both the brain and wing imaginal disc in the mutant larvae, but the average cell size is unchanged. There is an increase in apoptotic cells in the wing disc of the mutant larvae compared to controls.

The muscles and neuromuscular junctions of muscles 6-7 and 13-14 in the abdominal segments appear normal in larvae expressing mtTFB2^Scer\UAS.cAa under the control of Scer\GAL4^da.G32.