Homozygous larvae and adults show an impaired nociceptive heat response. Mutant larvae show a normal response to gentle touch. Mutant adults show normal geotactic climbing ability.
painEP2451 mutant adults have no alterations in aversive shock or temperature olfactory memory, compared to controls.
painEP2451/painEP2451 third instar larvae have significantly reduced turning frequency (locomotor defects) and significant defects in mechanical and thermal nociception.
painEP2451 mutant larvae completely lack a reaction to pain.
The number of times painEP2451 females reject males is significantly lower than that of wild-type females.
painEP2451 homozygous larvae have a severe mechanical nociception response deficit.
painEP2451 homozygous and heterozygous adults are defective in courtship long term memory (reduction in courtship activity 5 days after 7-hours conditioning) when compared to controls. painEP2451 homozygous adults exhibit normal courtship short term memory (reduction in courtship activity 30 minutes, 1 hour or 8 hours, but not 24 hours, after 1-hour conditioning) compared to controls.
Mutant third instar larvae show significant defects in nociception, having a significant reduction in the response frequency to noxious mechanical stimuli compared to control larvae. However, the navigational behaviours of the mutant larvae in response to gentle touch are not significantly different from wild type.
painEP2451 mutant flies exhibit problems with noxious temperature avoidance. They avoid surfaces heated up to 42[o]C but fail to avoid surfaces with temperatures at 42[o]C or above. Differences between wild-type and mutant temperature awareness are greatest at 46[o]C.
painEP2451 flies display weakened avoidance of the odorant 4-methyl-cyclohexanol, compared to wild-type controls, which display a strong avoidance for 4-methyl-cyclohexanol perfused air. When exposed to 4-methyl-cyclohexanol at lower concentrations, painEP2451 flies display the wild-type preference behavior, suggesting an alteration in response towards this odor.
painEP2451 mutant flies exhibit long-lasting male-male courtship behavior after recovery from mild CO[] anaesthesia, with a chaining index (i.e. the percentage of time these males spend courting one another and forming chains) higher than in wild-type flies.
painEP2451/painGAL4 trans-heterozygous flies exhibit strong male-male courtship behavior. In contrast, painEP2451/+ heterozygotes do not exhibit obvious male-male courtship behavior.
painEP2451/painEP2251 trans-heterozygous flies exhibit strong male-male courtship behavior.
at 25[o]C and 30[o]C, the performance of painEP2451 is similar to that of wild-type flies, However, the performance index, charting the avoidance to noxious heat is markedly lower in the mutant than in wild-type. This trend continues at 45[o]C and 50[o]C, indicating a defect in thermal nociception.
painEP2451 mutant larvae show a significant delay in response to noxious heat compared to control flies. These flies also exhibit a delay in their jump response to noxious heat of 17 seconds.
Mutant flies exhibit the wild type avoidance of aristolochic acid in food choice assays.
Mutant adults respond normally to subnoxious temperatures (39[o]C or less) but fail to avoid noxious heat (46[o]C), in contrast to wild-type controls.
Mutant larvae show an impaired thermal nociception response compared to controls.
Mutant larvae do not show the cardiac pauses during motion which are seen in wild-type larvae.
Basal cardiac activity (measured in anaesthetised animals) is increased in mutant larvae compared to wild-type controls.
Contractility of the heart tube is reduced in mutant larvae compared to wild-type controls.
The cardiac rhythm of mutant larvae is not modified by hypo-osmotic shock (in contrast to wild-type larvae).
The mating success rate, defined as the percentage of pairs that copulate, is significantly higher in painEP2451 homozygous females than wild-type. The time to copulation of painEP2451 mutant females is significantly shorter than that of controls. No significant difference is detected in the courtship latency or courtship index (defined as the percentage of time spent courting in a given observation period). These results show that painEP2451 mutant females do not elicit increased courtship behavior than control females, and that the rapid copulation of virgin painEP2451 mutant females is because of their enhanced receptivity.
No significant difference is observed in locomotion of painEP2451 mutant females compared to controls.
pain[EP2451] mutant seldom copulate with wingless males, suggesting that they can detect courtship songs.
painEP2451 mutants display impaired negative geotaxis behaviour.
The Johnston's organ of painEP2451 mutant flies show neural activity in response to body rotation that is indistinguishable from that of wild-type.
painEP2451 flies exhibit a reduced avoidance to isothiocyanate-containing food.
painEP2451 mutant flies do not show significant allyl- or benzl-isothiocyanate inhibition of sucrose-induced proboscis extension.
painEP2451 mutants exhibit normal avoidance to quinine and NaCl. They also exhibit wild-type levels of attraction to sucrose.
painEP2451 mutants exhibit wild-type levels of attraction to capsaicin.
painEP2451/painEP2621 trans-heterozygotes exhibit a reduced avoidance to isothiocyanate-containing food as in homozygous mutants.
painEP2451/painEP2451 flies show significantly longer jump latencies compared to wild type in a CO laser beam assay (thermal nociception induces a jump response) and in a heat plate assay (but show normal behavior in a jump test).
Larvae show normal thermotactic behaviour in a thermal preference assay.
Mutant larvae exhibit a defective response to noxious heat at 48oC, some failing to roll even after 10 seconds of stimulus. Animals do not display highly uncoordinated movement and poor viability. Larvae do exhibit a rapid response to noxious heat at 52oC. When stimulated with a 45mN fibre, only 13% of larvae responded with vigorous rolling (as compared to 92% for wild-type), however response to light touch is normal. However 81% of larvae respond to 100mN of stimulus. Mutant larvae tested for spiking of sensory afferents at room temperature exhibit normal mean bulk spiking frequencies. When the temperature is increased to 42oC the bulk spiking rate does not increase, (unlike in wild-type where the frequencies increase 2 to 3 fold).