Expression of cry^JF01880 under the control of Scer\GAL4^how-24B leads to a majority of flies dying during the late pupa stage, only about 2% of flies survive to adulthood and they die within three days post-eclosion. The cardiac tube in surviving adults is underdeveloped, irregular and smaller than controls, Z discs are immature and discontinuous, myofilament arrays are immature and irregular, and mitochondria are degenerated.

Flies expressing cry^JF01880 under the control of Scer\GAL4^how-24B display cardiac structure and function phenotypes during development. Heart rate of these flies is significantly lower than controls during L3 and pupal day 1 (but not L2 or pupal day 2) with the difference reappearing and becoming more pronounced between pupal day 3 and adult day 1; the cardiac activity period is significantly lower than controls during L2 stage and in pupal day 4 and adult day 1 (but not between L3 and pupal day 3); heart tube dimensions are significantly smaller than controls during pupal days 1, 2 and 3 and adult day 1 (but not L2, L3, or pupal day 4); and the cardiac developmental diastasis duration is significantly shorter.

Expression of cry^JF01880 under the control of Scer\GAL4^how-24B leads to disorganized cuticle morphologies, and increased, enlarged and disorganized denticle belts in the A6 and A7 segments of third instar larvae. Adults show disorganized and partially absent denticle belts in the A6 and A7 segments, and a smaller notum with disoriented bristles, as compared to controls.

Expression of cry^JF01880 under the control of Scer\GAL4^en.PU results in excess anterior crossvein, posterior crossvein and longitudinal wing veins, and a disorganized posterior L4 wing vein in adult wings compared to controls.