Data From: Dietary restriction extends lifespan across different temperatures in the fly
Data files
Mar 28, 2024 version files 282.88 KB
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EggCounting_18°Cand21°C_ywRflies.csv
6.25 KB
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Lifespan_18°Cand21°C_ywRflies.csv
154.83 KB
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Lifespan_25°C_ywRflies.csv
118.69 KB
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README.md
3.11 KB
Abstract
Dietary restriction (DR) has been consistently shown to extend lifespan across a range of taxa. However, recent findings question the universality of the DR longevity response, suggesting DR may not extend lifespan at lower temperatures in flies, and that the DR longevity response is an artifact of benign laboratory conditions.
We re-test this hypothesis, measuring the lifespan of Drosophila melanogaster at the lab-standard 25°C, and at colder temperatures (18°C and 21°C) across a range of 5 diets.
We found the DR longevity response to be robust, extending lifespan irrespective of temperature. Fecundity was measured as a positive control for the DR phenotype, and it was found that DR reduced egg laying.
We suggest results that question DR as a phenotype should not be overinterpreted readily, as variations in the experimental setup, genetic lines used, and diet-lifespan reaction norm may be responsible for discrepancies. Additionally, starting conditions that show a lifespan extension by DR and then changing the environment and/or genotype promises a more robust test of DR modulating factors.
README: Data From: Dietary restriction extends lifespan across different temperatures in the fly
We have submitted our raw data for our survival curves showing the longevity response of yw flies to dietary restriction at standard lab temperatures. (Lifespan_25°C_ywRflies.csv), cold temperatures (Lifespan_18°Cand21°C_ywRflies.csv), and their fecundity at cold temperatures (EggCounting_18°Cand21°C_ywRflies.csv). Data is presented in an accepted manuscript for Functional Ecology.
Descriptions
Lifespan Data
The following details are the same across both lifespan datasets:
- Individual: Cox proportional hazard model requires that each row in the dataset represents a single individual.
- Genotype: The code M22 is used by the lab to refer to a wild-type strain of Drosophila melanogaster known as ywR flies.
- Cage: Number assigned to the demography cage each fly was kept in. This was recorded so Cage could then be included as a random term in our Cox proportional hazard model.
- Age: The age at which each individual died (Days)
- At.Risk: Number of flies still alive in the demography cage at the point of the individual's death. This is included to be able to plot mortality risk if so required.
- Transfer: The age-matched cohort that each individual belonged to.
- Dead: A binary value of 1 or 0 represents whether or not the hazard (death) has occurred. Lifespan experiments concluded when all flies were dead.
The following details are specific to the named dataset:
Lifespan_25°C_ywRflies
- Treatment: The yeast content of fly diets (%).
- Experiment: Refers to the experiments included the survival curve shown in Fig.1. Each experiment is identified by the initials of the researcher who led the experiment and the corresponding experiment letter used in the survival curve.
- Lifespan_18°Cand21°C_ywRflies
- Treatment: Temperature condition for each individual (21 or 18 (°C)) followed by the yeast content of the fly diet (2,4,6,8 or 10 (%)).
- Egg Counting Data
EggCounting_18°Cand21°C_ywRflies
- Vial Date: Date when vials, containing food on which eggs were laid, were removed from demography cages. Vials were collected on two dates, considered to be roughly a midpoint in the lifespan of the fly populations at the highest yeast diets.
- Date counted: Date of manual counts of eggs laid in each vial. Eggs were stored at 4°C after collection and until they were counted to prevent eggs from hatching and therefore avoid miss-counts.
- Vial Number: Corresponds to the demography cages each vial was taken from.
- Temp: Temperature of each corresponding demography cage was kept at (°C).
- Conc: The yeast content of fly diets (%).
- Egg Count: Number of eggs per counted in each vial, including eggs on vial base and eggs on residual food on sides of vial.
- Age: Age of cohort of flies per demography cage at the time of vial collection, calculated using date flies eclosed (DOB).
- Females per Cage: Number of females per corresponding demography cage, used with Egg Count to calculate the number of Eggs per Female.