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Updated: Jun 17, 2026
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Measurement of Lifespan in Drosophila melanogaster
Published on: January 7, 2013
Polycomb Repressive Complex 2 and Trithorax modulate Drosophila longevity and stress resistance
Alex P Siebold1, Rakhee Banerjee, Feng Tie
1Department of Genetics, Case Western Reserve University, School of Medicine, Cleveland, OH 44106, USA.
Summary
Mutations in Polycomb Repressive Complex 2 (PRC2) proteins E(Z) and ESC extend lifespan and enhance stress resistance by reducing H3K27me3 levels. Trithorax (trx) mutations counteract these beneficial effects.
Area of Science:
- Epigenetics
- Molecular Biology
- Aging Research
Background:
- Polycomb Group (PcG) and Trithorax Group (TrxG) proteins are crucial epigenetic regulators controlling gene expression.
- These protein groups antagonistically modify chromatin, influencing diverse biological processes.
Purpose of the Study:
- To investigate the role of Polycomb Repressive Complex 2 (PRC2) subunits E(Z) and ESC in organismal longevity and stress resistance.
- To determine the impact of trithorax (trx) mutations on PRC2 mutant phenotypes.
Main Methods:
- Generating heterozygous mutations in E(Z) and ESC, core subunits of PRC2.
- Analyzing the effects of trithorax (trx) mutations on E(Z) and ESC mutants.
- Measuring trimethylated H3K27 (H3K27me3) levels.
- Assessing oxidative stress and starvation resistance.
- Examining the expression of Polycomb targets like Abd-B and Odc1.
Main Results:
- Heterozygous mutations in E(Z) or ESC increased longevity and stress resistance.
- These mutations led to reduced adult levels of trimethylated H3K27 (H3K27me3).
- Mutations in trithorax (trx) elevated H3K27me3 levels in E(z) mutants and suppressed their longevity and stress resistance.
- Long-lived mutants showed derepression of Polycomb targets Abd-B and Odc1.
Conclusions:
- PRC2 and TRX play significant roles in modulating organismal longevity and stress resistance.
- Reduced H3K27me3 levels and perturbed Polycomb silencing are responsible for the longevity and stress resistance phenotypes observed in PRC2 mutants.
- Moderate disruption of Polycomb silencing can extend lifespan.
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