Splice junction defect.
One nucleotide displacement of the 3' AG splice site at the intron preceding exon 6b1, resulting in the failure to produce all exon 6b1-containing isoforms.
G18109571A
G?A
One nucleotide displacement of the 3' AG splice site at the intron preceding exon 6b1, resulting in the failure to produce all exon 6b1-containing isoforms.
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
wupAhdp-3 mutants exhibit held-up wings.
During the development of indirect flight muscle fibres, wupAhdp-3 mutant pupal myoblasts fuse with dorsal medial muscle templates as in wild-type pupa. Following fusion, myotube formation and fibre shortening takes place but elongation of fibres fails to occur, leaving wupAhdp-3 myotubes shorter than in wild type. While wild-type muscle fibres extend completely to form the cuticle, wupAhdp-3 mutant dorsal medial muscle fibres are pulled from their attachment sites and start to degrade; with time, complete degradation occurs resulting in newly eclosed adults with no fibres. At 40-42 hours after pupal formation (APF) wupAhdp-3 mutant myofibrils are clumped as filamentous bundles with no clear sarcomere-like structures and with visible thick and thin filaments that are scattered without regular structure, in contrast to wild-type myofibrils, which consist of thick and thin filaments assembled into clearly demarcated repetitive I-A-I bands. At this time, wild-type myofibrils exhibit uniform length sarcomeres demarcated by straight, electron-dense Z-discs, while wupAhdp-3 mutant myofibrils have no Z-discs but contain stress-fibre-like structures, the usual precursor of Z-discs. These are abnormally large and may contain Z-disc-like electron dense bodies. By 46-48 hours APF, wupAhdp-3 mutants have no Z-discs or sarcomeres. Heterozygous wupAhdp-3 mutant indirect flight muscle fibres show a hypercontraction muscle phenotype in which the muscles are pulled to one of the attachment sites starting from the middle of the fibres. No such contraction is seen in wild-type controls. The outer areas of the wupAhdp-3 heterozygote myofibrils have loosely packed thick-thin filaments and contain Z-discs and M-lines that appear streamed compared to wild type. The thorax of wupAhdp-3 homozygous mutant flies has no visible indirect flight muscle or tergal depressor of trochanter muscle.
100% of wupAhdp-3/Y adults have an upheld wing phenotype. The indirect flight muscles fail to form and only small muscle remnants are seen in the thoraces of later pupal and adult stages.
Flight muscles show abnormalities not long after myoblast fusion, partially elongate and only small muscle remnants remain in later pupae.
IFM phenotype cannot be suppressed by wupAD3.
Wings are held up vertically, flies do not jump and walk weakly. Fibrillar muscles (dorsal-longitudinal muscle, DLM and dorso-ventral muscle, DVM) are reduced and the tergal depressor of trochanter muscle (TDT) is defective. Heterozygotes with wupA8384 have only remnants of the degenerating fibrillar muscles and no (TDT).
Extreme allele. The development of the DLM, DVM and TDT muscles is aborted. Newly eclosed adults show occasional remnants of muscle tissue without any trace of sarcomeric organization. All other somatic and visceral muscles appear normal in structure. wupAhdp-3/+ show abnormal muscle structure and function, wupAhdp-3/Y; Dp(1;3)JC153/+ are wild type but wupAhdp-3/Y; Dp(1;3)JC153/Dp(1;3)JC153 flies are unable to jump or fly (and show reduced viability, though their muscle histology and wing position are normal).
In flight muscles of recently eclosed adults myofibrils are missing. Thick and thin filaments are present in the sarcoplasm though normal Z discs are not evident.
Flies are flightless and hold their wings in an abnormal position, and sometimes show variable jump ability.
wupAhdp-3 has visible | adult stage phenotype, suppressible by Dp(1;2)CH322-143G12
wupAhdp-3 has flightless phenotype, suppressible by Dp(1;3)JC153
wupAhdp-3 has flightless phenotype, suppressible by Dp(1;2)CH322-143G12
wupAhdp-3 has visible | adult stage phenotype, suppressible by Dp(1;3)JC153
wupAhdp-3 has lethal | recessive phenotype, non-suppressible by mir-969sponge.V2.UAS.mCherry/Scer\GAL4αTub84B.PL
l(1)16Fe1, wupAhdp-3 has abnormal flight | dominant phenotype
wupAhdp-3 has indirect flight muscle cell phenotype, suppressible by Mhc12/Mhc2F
wupAhdp-3 has indirect flight muscle cell phenotype, suppressible by Mhc12/Mhc12
wupAhdp-3 has indirect flight muscle cell phenotype, suppressible by Mhc12/MhcD62
wupAhdp-3 has indirect flight muscle cell phenotype, non-suppressible by Mhc12/Mhc2D
wupAhdp-3 has indirect flight muscle cell phenotype, non-suppressible by Mhc12/Mhc2F
wupAhdp-3 has indirect flight muscle cell phenotype, non-suppressible by MhcD1/Mhc12
wupAhdp-3 has indirect flight muscle cell phenotype, non-suppressible by Mhc12/MhcD41
wupAhdp-3 has indirect flight muscle cell phenotype, non-suppressible by Mhc12/MhcD45
wupAhdp-3 has indirect flight muscle cell phenotype, non-suppressible by Tm2D53
wupAhdp-3 is a suppressor | partially of indirect flight muscle cell phenotype of Rbfox1RNAi.UAS, Scer\GAL4Mef2.PR
wupAhdp-3 is a suppressor | partially of muscle cell | decreased number phenotype of Rbfox1RNAi.UAS, Scer\GAL4Mef2.PR
wupAhdp-3 is a suppressor | partially of dorsal longitudinal indirect flight muscle cell phenotype of Rbfox1RNAi.UAS, Scer\GAL4Mef2.PR
l(1)16Fe1, wupAhdp-3 has adult somatic muscle cell phenotype
l(1)16Fe23437, l(1)16Fm23437, wupAhdp-3 has adult somatic muscle cell phenotype
Mhc7, wupAhdp-3 has striated muscle thin filament phenotype
Mhc10/Mhc10 flies expressing MhcR57-24.Act88F completely restore indirect flight muscle fibre defects to a normal structural condition in wupAhdp-3/+ flies.
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.
In wupAhdp-3/Y; Mhc10/Mhc10; MhcR57-24.Act88F flies thick filaments, some thin filaments, isolated Z-discs and tiger-tails are readily visible but sarcomeric structures fail to assemble.
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.
Z disc morphology is improved in the double mutant with Mhc7. Thin filaments are reduced, even in the absence of myosin.
wupAhdp-3 is partially rescued by wupAUASp.B/Scer\GAL4αTub84B.PL
wupAhdp-3 is partially rescued by wupAUAS.L9/Scer\GAL4Hk-UH3
wupAhdp-3 is not rescued by wupAUASp.A/Scer\GAL4αTub84B.PL
wupAhdp-3 is not rescued by Scer\GAL4αTub84B.PL/wupAUASp.C
wupAhdp-3 is not rescued by wupAUASp.D/Scer\GAL4αTub84B.PL
wupAhdp-3 is not rescued by wupAUASp.E/Scer\GAL4αTub84B.PL
wupAhdp-3 is not rescued by wupAUASp.F/Scer\GAL4αTub84B.PL
wupAhdp-3 is not rescued by wupAUASp.G/Scer\GAL4αTub84B.PL
wupAhdp-3 is not rescued by Scer\GAL4αTub84B.PL/wupAUASp.H
wupAhdp-3 is not rescued by wupAUASp.I/Scer\GAL4αTub84B.PL
wupAhdp-3 is not rescued by wupAUASp.J/Scer\GAL4αTub84B.PL
wupAhdp-3 is not rescued by wupAUASp.K/Scer\GAL4αTub84B.PL
wupAhdp-3 is not rescued by wupAfTRG00925.sfGFP-TVPTBF
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.
Mutant muscle phenotype is due to lack of one or more TnI isoforms.