Deletion of the 5' flanking and 5' coding regions.
Large deletion encompassing most of the transcription unit and a large upstream region.
rhabdomere & actin filament
The loss of retinal response to light displayed by ninaE17 homozygotes and by ninaE17, norpA36 double homozygotes that also contain a copy of norpAninaE.PW is suppressed by the expression of Rh7Scer\UAS.cNa under the control of Scer\GAL4ninaE.PT.
Flies expressing norpAninaE.PM in norpA36 ninaE17/ninaE17 background exhibit a dramatically reduced response to light (lack of a light induced depolarization and on and off transients) than controls in electroretinogram readings although they are stimulated with higher light intensity than controls.
Vps261 ninaE17 double mutants display significant suppression of the ERG and photoreceptor cell defects seen in Vps261 single mutant flies that have been kept in a 12-hour Light/Dark cycle for 4 days.
Expression of 5-HT2DCIII.Scer\UAS under the control of Scer\GAL4ninaE.PT does not rescue the ability of ninaE17 larvae to strongly discriminate between 18[o]C and 24[o]C in a binary choice thermotaxis assay.
The retrainment of ninaE17 Rh61 cryb to 6 hour delayed green light (472-603nm) and Y-FL (475-724nm) is significantly slower than that of ninaE17 cryb mutants. Indeed some flies do not adapt to the new photoperiod within 7 days.
Rh3Rh1+3, ninaE17 flies exhibit a shift in the point of equiluminance such that, compared with wild-type flies much less blue light is required to balace the standard green intensity, giving a blue/green ratio of 0.017 compared with 0.40 for wild-type flies.
CDaseScer\UAS.cAa (driven by Scer\GAL4GMR.PF) enhances the rhabdomere phenotype seen in ninaE17 animals. Very few rhabdomeric elements remain at the apical surface of the photoreceptors in three day old animals of this genotype. Most of the rhabdomeric membranes are internalised and are in the process of being cleared. When CDaseScer\UAS.cAa is driven by Scer\GAL4hs.PB and expressed in ninaE17 flies (under heat shock) just after eclosion, most of the rhabdomere is cleared from the apical region, unlike the phenotype seen in ninaE17 animals alone.
norpA36 ; ninaE17/+ flies that carry norpAninaE.PM have a robust response to light at both 350nm and 520nm (measured using an electroretinogram (ERG) recording). norpA36 ; ninaE17/ninaE17 flies that carry norpAninaE.PM have no response to light at both 350nm and 520nm (measured using an ERG recording). Introduction of Lpol\Ops1ninaE.PK or Lpol\Ops1ninaE.T:Btau\1D4 into a norpA36 ; ninaE17/ninaE17 ; norpAninaE.PM background restores the response to light (measured using an ERG recording), although the response at 520nm is much great than that at 350nm. Flies expressing Lpol\Ops1ninaE.PK in a ninaE17 Gα49B1 background show no response to light (measured using an ERG recording). Flies expressing Lpol\Ops1ninaE.T:Btau\1D4 in a ninaE17 Gα49B1 background show no response to light (measured using an ERG recording). Flies expressing Lpol\Ops1ninaE.PK in a ninaE17 norpA36 background show no response to light (measured using an ERG recording). Flies expressing Lpol\Ops1ninaE.T:Btau\1D4 in a ninaE17 norpA36 background show no response to light (measured using an ERG recording).
Expression of Rac1V12.C.Scer\UAS under the control of Scer\GAL4hs.PB during rhabdomere morphogenesis substantially rescues rhabdomere morphogenesis in ninaE17 mutants. Occasional loops of rhabdomere membrane are seen intruded into the photoreceptor, but most terminate at a well-defined base. The rhabdomere terminal web (RTW) is more tightly organised. Substantial rescue is seen 5 days after eclosion. About 18% of R1-R6 rhabdomeres are rescued in non-heat shocked animals, rising to 90% in animals heat shocked at 80% of pupal development.
Expression of Rh5ninaE.PC restores normal light response, ERGs display a robust response to light with normal on and off transients and a maintained depolarisation with a large amplitude.
Expression of Mmus\Opn4ninaE.PS partially suppresses the reduced rhabdomere size observed in ninaE17 mutants, although the rhabdomeres also show deformed structure, and abnormal actin localization, as compared to wild type. Flies expressing Mmus\Opn4ninaE.PS in a ninaE17 background also exhibit defects in photoreceptor light induced currents, with reduced sensitivity to light stimuli, and abnormal continuous production of quantum bump-like unitary currents, as compared to wild type.
Btau\RHOninaE.PA is able to partially rescue the rhabdomere defects of ninaE17 flies. At 3 days of age, rhabdomere size is largely rescued, although they are smaller and slightly irregular in shape compared to wild type. At 7 days, more substantial defects in rhabdomere packing are seen in the rescued flies, and at 14 days the rhabdomere membranes are extensively unraveled. The unraveling phenotype is seen in 14 day old rescued flies raised both under light-dark conditions and raised under constant darkness.
Expression of either ninaE::Btau\RHORHOC2.ninaE or ninaE::Btau\RHORHOC3.ninaErescues the rhabdomere defects of ninaE17 flies. The rescued flies show excellent rhabdomere morphology at 7 days after eclosion and ommatidial structure remains intact in 14 day old flies.
7 day old ninaE17 flies expressing ninaE::Btau\RHORHOCt.ninaE have reduced rhabdomeres that are irregular in shape compared to wild type. At 14 days after eclosion, some photoreceptors lacking a visible rhabdomere are observed.
ninaEAAXXA significantly rescues the collapsing of the closely apposed membrane inside the cells that is seen in ninaE17 photoreceptors. However, there are numerous vesicles occupying the sub-rhabdomeric space.
Expression of ninaEScer\UAS.cSa under the control of either Scer\GAL4ninaE.PT or Scer\GAL4TrpA1.PR rescues the thermotaxis behaviour of ninaE17 larvae, such that the rescued larvae strongly prefer 18[o]C over 24[o]C in a binary choice thermotaxis assay.