indirect flight muscle & myofibril
indirect flight muscle & myotube
indirect flight muscle & sarcomere
indirect flight muscle & striated muscle thick filament
indirect flight muscle & striated muscle thin filament
indirect flight muscle & Z disc
The thorax of wupAhdp-3/Y; Mhc10/+ flies have a small bunch of visible muscle mass, in contrast to wupAhdp-3 ; Mhc+/+ flies which have no visible indirect flight muscle. wupAhdp-3/Y; Mhc10/+ flies that express one copy of MhcR57-24.Act88F show a greater increase in muscle mass. This increase is greater still when flies express two copies of MhcR57-24.Act88F. Only in wupAhdp-3/Y; Mhc10/Mhc10 flies that express two copies of MhcR57-24.Act88F can actual myofibrillar structures be seen.
In the thorax of wupAhdp-3/Y; Mhc7/Mhc2B flies there is an absence of myofibrils and no clear areas of interdigitated thick-thin filaments. There are visible "tiger-tail" structures formed by condensed serially repeated Z-discs connected by short stretches of thin filaments.
41% of wupAhdp-3/Y ; Mhc12/Mhc12 flies have an upheld wing phenotype and 59% hold their wings normally. 41% of wupAhdp-3/Y ; Mhc12/Mhc2D flies have an upheld wing phenotype and 59% hold their wings normally. 61% of wupAhdp-3/Y ; Mhc12/MhcD45 flies have an upheld wing phenotype and 39% hold their wings normally. The indirect flight muscles of wupAhdp-3/Y ; Mhc12/Mhc2B and wupAhdp-3/Y ; Mhc12/Mhc2F flies show a partial hypercontraction phenotype.
l(1)16Fe1 fails to complement wupAhdp-3 with respect to wing position, flight and jump behaviour and muscle structure. The '23437' chromosome (in which l(1)16Fm and l(1)16Fe are affected) fails to complement wupAhdp-3, resulting in severe muscle defects.
Expression of wupAScer\UAS.L9 under the control of Scer\GAL4Hk-UH3 rescues the structural defects seen in the indirect flight muscles of hemizygous wupAhdp-3 mutants, though not completely. Rescued hemizygous flies are completely flightless and the size of the myofibrils is comparatively smaller compared to controls. Rescued heterozygous flies show a better myofibrillar structure where the sarcomeres look near-normal, but are still unable to fly.