Expression of DAAM^{dsRNA.Scer\UAS.T129M} under the control of Scer\GAL4^UH3 (in the presence of Dcr-2^Scer\UAS.cDa to enhance RNAi efficiency) results in 87.1 +/- 3.9% of adults being flightless.

Expression of DAAM^{dsRNA.Scer\UAS.T129M} under the control of Scer\GAL4^UH3 (in the presence of Dcr-2^Scer\UAS.cDa to enhance RNAi efficiency) in a DAAM^Ex1 background results in 98.9 +/- 1.1% of adults being flightless.

Flies expressing DAAM^{dsRNA.Scer\UAS.T129M} under the control of Scer\GAL4^UH3 (in the presence of Dcr-2^Scer\UAS.cDa in a DAAM^Ex1 background show gross alterations in indirect flight muscle morphology. The myofibrils are thinner than normal, irregularly shaped and have frayed edges. Shortened sarcomeres are seen. There is a reduction in F-actin staining without a significant change in the amount of G-actin. M-lines are absent and strong Z-disc defects are seen. Thick filaments rarely run parallel to each other, the average number of thick filaments per sarcomere is strongly reduced and filament packing is much looser than normal. The organisation of thin filaments is very different from wild type. These defects are already seen at 48 hours after puparium formation at 29[o]C. The elasticity (Young's modulus) of the mutant myofibrils is significantly lower than that of wild type.