NnaD^PL90 mutants hatch from their eggs in normal numbers with no defects in cuticle patterning. However, NnaD^PL90 third instar larvae are much thinner than their control siblings. NnaD^PL90 males die between the late second instar larval stage and early pupal stage. NnaD^PL90 mutants that survive to produce pupal cases initiate morphogenesis but die before head eversion. Almost all NnaD^PL90 male flies that survive past head eversion do complete morphogenesis, and then eclose as "escaper" males. The frequency of escaper NnaD^PL90 males is approximately 40% of expected Mendelian ratios. The cuticles of NnaD^PL90 escaper males are normal, but the wings are smaller than those of controls and always appear droopy and opaque.

Charting of NnaD^PL90 escaper male lifespan reveals continuous, relatively uniform, and decreased survival, suggesting that there isn't a particular crisis stage or time-dependent nature to their demise.

18-day old NnaD^PL90 male fly heads do not display evidence of vacuolization or gross neurodegeneration in the brain parenchyma. However, areas of thinning, cell loss, and vacuole formation in retinal photoreceptor neurons are found. Two-day old NnaD^PL90 mutant heads exhibit less severe photoreceptor degeneration. The ommatidial array is severely disrupted in 5-day old NnaD^PL90 escaper males retina.

Four-day old NnaD^PL90 escaper males score extremely poorly on the Benzer countercurrent assay for phototaxis, indicating a severe loss of eyesight.

Seven-day old NnaD^PL90 escaper males exhibit a number of electron-dense degenerating retina cells, typical of apoptosis. Endoplasmic reticulum, highly studded with ribosomes in neurons at moderate to advanced stages of degeneration are also found. Unlike mitochondria with well-defined cristae and lumens of normal size, NnaD^PL90 mitochondria exhibit decreased numbers of cristae, and the lumens of the cristae are swollen and irregular. Many NnaD^PL90 mitochondria have vacuoles, a feature never seen in wild-type.

Mitochondrial complex I, II and V exhibit marked reductions in activity in NnaD^PL90 larval samples. NnaD^PL90 flies exhibit significantly decreased survival when exposed to 2,4-dinitrophenol at either a high or a low concentration. NnaD^PL90 escaper males are exquisitely susceptible to oligomycin at high concentrations, but, at low concentrations, both NnaD^PL90 and control flies are resistant, suggesting a distinct threshold for toxicity.

Nna1^PL90 has abnormal visual behavior phenotype, suppressible by BacA\p35^UAS.cHa/Scer\GAL4^ey.PU

Nna1^PL90 has abnormal visual behavior phenotype, non-suppressible by Avic\GFP^UAS.cUa/Scer\GAL4^ey.PU