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mtm-3

C. elegans

Phosphatidylinositol-3,5-bisphosphate 3-phosphatase MTMR3

What the model saw

Gene: mtm-3
Organism: Caenorhabditis elegans
Known functions: Phosphatidylinositol-3,5-bisphosphate 3-phosphatase MTMR3. inositol bisphosphate phosphatase activity. metal ion binding. phosphatidylinositol trisphosphate phosphatase activity. phosphatidylinositol-3,5-bisphosphate 3-phosphatase activity. phosphatidylinositol-3,5-bisphosphate phosphatase activity. phosphatidylinositol-3-phosphate phosphatase activity.
View unredacted entry
Phosphatidylinositol-3,5-bisphosphate 3-phosphatase MTMR3. inositol bisphosphate phosphatase activity. metal ion binding. phosphatidylinositol trisphosphate phosphatase activity. phosphatidylinositol-3,5-bisphosphate 3-phosphatase activity. phosphatidylinositol-3,5-bisphosphate phosphatase activity. phosphatidylinositol-3-phosphate phosphatase activity.

Solver output

Predicted influence
Anti-longevity
Confidence
72%
Mechanism
Disabled macroautophagy
Reasoning

mtm-3 encodes a myotubularin-related phosphatase (MTMR3 ortholog) that dephosphorylates phosphatidylinositol-3-phosphate (PI3P) and phosphatidylinositol-3,5-bisphosphate (PI(3,5)P2). PI3P is an essential lipid second messenger generated by the class III PI3-kinase VPS-34, which is required for autophagosome nucleation and maturation. By hydrolyzing PI3P, mtm-3 directly antagonizes the pro-autophagic PI3K/VPS-34 signaling axis, reducing autophagic flux. Additionally, PI(3,5)P2 is critical for late endosome/lysosome function and autophagosome-lysosome fusion; its degradation by mtm-3 further impairs autophagic clearance. Since robust autophagy is a well-established pro-longevity mechanism in C. elegans (e.g., downstream of DAF-16/FOXO and dietary restriction), a phosphatase that suppresses PI3P availability would be expected to shorten lifespan. Furthermore, PI3P/PI(3,5)P2 also feed into nutrient-sensing pathways, and their reduction could impair lysosomal mTORC1 regulation.

Key pathways
PI3P-dependent autophagy (VPS-34/Beclin axis)PI(3,5)P2-mediated lysosome/late endosome functionDAF-16/FOXO pro-longevity autophagic signaling
Longevity influence
Pro-longevity
Lifespan effect
Decrease

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
Incorrect
Mechanism
Incorrect
Reasoning quality
2/5
Failure mode
Confident wrong
Notes

The model predicted anti_longevity with 0.72 confidence, but the ground truth is pro_longevity. The model's reasoning is logically coherent but leads to the wrong conclusion. The model assumed that because mtm-3 dephosphorylates PI3P (antagonizing autophagy), it would shorten lifespan. However, the actual experimental data shows mtm-3 is pro-longevity. This could be because myotubularin phosphatases in C. elegans may regulate PI3K/AKT/DAF-16 signaling differently than expected - by reducing PI3P, mtm-3 may actually inhibit the pro-aging insulin/IGF-1 signaling pathway (which requires PI3P for AKT activation), thereby extending lifespan. The model's reasoning about autophagy suppression is plausible in isolation but misses the more dominant effect of PI3P reduction on the insulin/IGF-1 pathway. The model was confidently wrong and did not consider alternative mechanisms by which PI3P reduction could be pro-longevity.

Raw API responses

solver

{
  "reasoning": "mtm-3 encodes a myotubularin-related phosphatase (MTMR3 ortholog) that dephosphorylates phosphatidylinositol-3-phosphate (PI3P) and phosphatidylinositol-3,5-bisphosphate (PI(3,5)P2). PI3P is an essential lipid second messenger generated by the class III PI3-kinase VPS-34, which is required for autophagosome nucleation and maturation. By hydrolyzing PI3P, mtm-3 directly antagonizes the pro-autophagic PI3K/VPS-34 signaling axis, reducing autophagic flux. Additionally, PI(3,5)P2 is critical for late endosome/lysosome function and autophagosome-lysosome fusion; its degradation by mtm-3 further impairs autophagic clearance. Since robust autophagy is a well-established pro-longevity mechanism in C. elegans (e.g., downstream of DAF-16/FOXO and dietary restriction), a phosphatase that suppresses PI3P availability would be expected to shorten lifespan. Furthermore, PI3P/PI(3,5)P2 also feed into nutrient-sensing pathways, and their reduction could impair lysosomal mTORC1 regulation.",
  "confidence": 0.72,
  "key_pathways": [
    "PI3P-dependent autophagy (VPS-34/Beclin axis)",
    "PI(3,5)P2-mediated lysosome/late endosome function",
    "DAF-16/FOXO pro-longevity autophagic signaling"
  ],
  "mechanism_class": "disabled_macroautophagy",
  "longevity_influence": "anti_longevity"
}

advisor

{
  "notes": "The model predicted anti_longevity with 0.72 confidence, but the ground truth is pro_longevity. The model's reasoning is logically coherent but leads to the wrong conclusion. The model assumed that because mtm-3 dephosphorylates PI3P (antagonizing autophagy), it would shorten lifespan. However, the actual experimental data shows mtm-3 is pro-longevity. This could be because myotubularin phosphatases in C. elegans may regulate PI3K/AKT/DAF-16 signaling differently than expected - by reducing PI3P, mtm-3 may actually inhibit the pro-aging insulin/IGF-1 signaling pathway (which requires PI3P for AKT activation), thereby extending lifespan. The model's reasoning about autophagy suppression is plausible in isolation but misses the more dominant effect of PI3P reduction on the insulin/IGF-1 pathway. The model was confidently wrong and did not consider alternative mechanisms by which PI3P reduction could be pro-longevity.",
  "failure_mode": "confident_wrong",
  "answer_correct": false,
  "mechanism_correct": false,
  "reasoning_quality": 2,
  "ground_truth_questionable": false
}