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E(z)

D. melanogaster

Enhancer of zeste

What the model saw

Gene: E(z)
Organism: Drosophila melanogaster
Known functions: Enhancer of zeste. enhancer of zeste. DNA binding. chromatin binding. histone H3K27 methyltransferase activity. histone H3K27 trimethyltransferase activity. histone H3K9 methyltransferase activity. histone methyltransferase activity. protein binding. protein-lysine N-methyltransferase activity. sequence-specific DNA binding.
View unredacted entry
Enhancer of zeste. enhancer of zeste. DNA binding. chromatin binding. histone H3K27 methyltransferase activity. histone H3K27 trimethyltransferase activity. histone H3K9 methyltransferase activity. histone methyltransferase activity. protein binding. protein-lysine N-methyltransferase activity. sequence-specific DNA binding.

Solver output

Predicted influence
Anti-longevity
Confidence
75%
Mechanism
Epigenetic alterations
Reasoning

E(z) is the catalytic subunit of the Polycomb Repressive Complex 2 (PRC2) in Drosophila, responsible for mono-, di-, and trimethylation of histone H3 at lysine 27 (H3K27me1/2/3). H3K27me3 is a repressive chromatin mark that silences developmental genes, including key longevity-promoting pathways. During aging, H3K27me3 levels globally increase and redistribute, contributing to aberrant transcriptional silencing of genes involved in stress response, proteostasis, and metabolic regulation. Studies in Drosophila have shown that reducing E(z)/PRC2 activity extends lifespan, consistent with the idea that its normal function — depositing repressive H3K27 methylation marks — progressively silences pro-longevity gene programs. Additionally, its H3K9 methyltransferase activity further reinforces heterochromatin-based gene silencing, compounding age-associated epigenetic drift.

Key pathways
PRC2-mediated H3K27me3 repressive chromatin silencingPolycomb group transcriptional repressionH3K9 methylation and heterochromatin formation
Longevity influence
Anti-longevity
Lifespan effect
Increase

GenAge curators classify each gene's normal function as promoting (Pro-Longevity) or opposing (Anti-Longevity) longevity, based on synthesis across studies. Loss-of-function effects can vary from this depending on the manipulation.

Advisor judgment

Answer
Correct
Mechanism
Correct
Reasoning quality
4/5
Failure mode
Correct
Notes

The model correctly predicted anti_longevity for E(z) in Drosophila. The mechanistic reasoning is sound and well-grounded: E(z) as the catalytic subunit of PRC2 deposits H3K27me3 repressive marks, and reducing its activity has been shown to extend lifespan in Drosophila. The model correctly identifies the epigenetic mechanism and the relevant pathways. The confidence of 0.75 is appropriate. Minor note: the claim that H3K27me3 levels "globally increase" during aging is somewhat contested and context-dependent, but the overall reasoning is solid and consistent with published literature on PRC2/E(z) and aging in Drosophila.

Raw API responses

solver

{
  "reasoning": "E(z) is the catalytic subunit of the Polycomb Repressive Complex 2 (PRC2) in Drosophila, responsible for mono-, di-, and trimethylation of histone H3 at lysine 27 (H3K27me1/2/3). H3K27me3 is a repressive chromatin mark that silences developmental genes, including key longevity-promoting pathways. During aging, H3K27me3 levels globally increase and redistribute, contributing to aberrant transcriptional silencing of genes involved in stress response, proteostasis, and metabolic regulation. Studies in Drosophila have shown that reducing E(z)/PRC2 activity extends lifespan, consistent with the idea that its normal function — depositing repressive H3K27 methylation marks — progressively silences pro-longevity gene programs. Additionally, its H3K9 methyltransferase activity further reinforces heterochromatin-based gene silencing, compounding age-associated epigenetic drift.",
  "confidence": 0.75,
  "key_pathways": [
    "PRC2-mediated H3K27me3 repressive chromatin silencing",
    "Polycomb group transcriptional repression",
    "H3K9 methylation and heterochromatin formation"
  ],
  "mechanism_class": "epigenetic_alterations",
  "longevity_influence": "anti_longevity"
}

advisor

{
  "notes": "The model correctly predicted anti_longevity for E(z) in Drosophila. The mechanistic reasoning is sound and well-grounded: E(z) as the catalytic subunit of PRC2 deposits H3K27me3 repressive marks, and reducing its activity has been shown to extend lifespan in Drosophila. The model correctly identifies the epigenetic mechanism and the relevant pathways. The confidence of 0.75 is appropriate. Minor note: the claim that H3K27me3 levels \"globally increase\" during aging is somewhat contested and context-dependent, but the overall reasoning is solid and consistent with published literature on PRC2/E(z) and aging in Drosophila.",
  "failure_mode": "correct",
  "answer_correct": true,
  "mechanism_correct": true,
  "reasoning_quality": 4,
  "ground_truth_questionable": false
}