EcR^NP5219/+ flies have reduced amounts of daytime sleep compared to controls. The reduction is greater in females than in males. The amount of nighttime sleep in EcR^NP5219/+ mutants is similar to controls.

EcR^A483T/EcR^NP5219 transheterozygotes are lethal during development at 25[o]C but survive to adulthood if raised at 18[o]C.

Total daytime sleep in EcR^A483T/EcR^NP5219 mutants raised at 18[o]C and transferred to 25[o]C 3 days after eclosion is reduced by 56% in females and 61% in males. Nighttime sleep is also reduced (7% and 11% in females and males respectively).

Average sleep bout duration is reduced in male and female EcR^A483T/EcR^NP5219 flies both during the day and at night. The maximum sleep bout duration is also reduced compared to wild type, most significantly during the daytime.

Wake bout duration is similar to controls in both male and female EcR^A483T/EcR^NP5219 mutants. Waking activity is reduced during the day in both sexes. No difference in waking activity is seen at night.

EcR^A483T/EcR^NP5219 mutants female flies regain less sleep than controls following 12 hours of sleep deprivation whereas males regain more sleep. The increase in average sleep bout duration seen in controls following sleep deprivation does not occur in either male of female mutants.

Trained heterozygous EcR^NP5219 mutant males display normal courtship short-term memory in behavioural assays, but are defective in long-term memory.