Indy206 homozygotes demonstrate a significant life span extension.
There is a strong relationship between life span extension in Indy206 mutants and calorie restriction. At normal or high calorie conditions Indy206 heterozygote flies have a significant life span extension as compared to genetically matched controls. However, under low calorie conditions, Indy206 heterozygote mutant flies show minimal lifespan extension.
Long-lived Indy206 heterozygote flies living on high-calorie food are as sensitive to starvation stress as normal flies on a low-calorie food. Indy206 heterozygote long-lived flies on high-calorie food gain very little weight and thus have a similar lack of weight gain as normal control flies on low-calorie food. Indy206 heterozygote flies on high-calorie food store less lipids than normal flies living on high calorie-food conditions.
Indy206 flies that have been backcrossed to yw flies for more than 10 generations still display a significant life span extension as compared to genetically matched controls when grown on normal rich food. There is no life span extension when Indy206 is backcrossed into the w1118 background.
Indy206 long-lived heterozygote flies living on high-calorie food show an increase in spontaneous physical activity that matches the increased physical activity seen with wild-type flies on low-calorie food.
There is no difference in food intake between Indy206 heterozygotes and wild-type flies.
Heterozygous females and males do not show an extended lifespan (after correction for genetic and cytoplasmic background effects).
Homozygous mutants are long lived, but have normal metabolic rates and flight velocity. Mutant flies have higher fecundity than wild-type early in life when fed on high quality food, also having a higher total life-time egg production. When on low-calorie food though fecundity is significantly decreased.
Heterozygotes show an increase in mean life-span to 71 days (compared to 37 days for controls) at 25oC, an extension in mean life-span of 92%. Extension of 1% maximal life-span is greater than 45%. At 18oC, the increase in mean life-span in mutants approaches 100% and the increase in 1% maximum life-span approaches 50% compared to controls. Heterozygous males and females are normal or superior in fertility and fecundity. Heterozygous females show the same early peak of egg laying and fertility as control females but sustain the ability to produce larger numbers of offspring for a longer period of time.
Indy[+]/Indy206, Scer\GAL4DJ651 is a suppressor of short lived phenotype of Ctet\tetXTNT-LC.UAS, Scer\GAL4DJ651
The reduced lifespan seen in males expressing Ctet\TeTxLCTNT.Scer\UAS under the control of Scer\GAL4DJ651 can be increased if the males also carry Indy206/+. Only a small increase in lifespan is seen in females expressing Ctet\TeTxLCTNT.Scer\UAS under the control of Scer\GAL4DJ651 and carrying Indy206/+.
The reduced lifespan seen in males expressing Ctet\TeTxLCTNT.Scer\UAS under the control of Scer\GAL4DJ651 can be suppressed if the males also carry Indy206/+. Only a small increase in lifespan is seen in females expressing Ctet\TeTxLCTNT.Scer\UAS under the control of Scer\GAL4DJ651 and carrying Indy206/+.
Excision of the P{lacW} element can revert the increased life-span phenotype.