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cth-2

C. elegans

Putative cystathionine gamma-lyase 2

What the model saw

Gene: cth-2
Organism: Caenorhabditis elegans
Known functions: Putative cystathionine gamma-lyase 2. cystathionine gamma-lyase activity. pyridoxal phosphate binding.
View unredacted entry
Putative cystathionine gamma-lyase 2. cystathionine gamma-lyase activity. pyridoxal phosphate binding.

Solver output

Predicted influence
Pro-longevity
Confidence
72%
Mechanism
Other
Reasoning

Cystathionine gamma-lyase (CSE) catalyzes the transsulfuration pathway step converting cystathionine to cysteine, and is a major enzymatic source of hydrogen sulfide (H₂S) in many organisms. H₂S is a gasotransmitter with well-established cytoprotective and pro-longevity effects: it activates stress-response pathways (including DAF-16/FOXO and Nrf2/SKN-1), enhances mitochondrial function at low concentrations, and reduces oxidative damage. In C. elegans, the transsulfuration pathway feeds into cysteine and glutathione biosynthesis, supporting antioxidant capacity and proteostasis. Pyridoxal phosphate (PLP) binding confirms the canonical enzymatic mechanism of this PLP-dependent lyase. Increased H₂S production via CSE activity has been linked to lifespan extension in multiple model organisms, including nematodes.

Key pathways
transsulfuration pathway / hydrogen sulfide productionglutathione biosynthesis and antioxidant defenseDAF-16/FOXO stress response 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
Correct
Mechanism
Correct
Reasoning quality
4/5
Failure mode
Correct
Notes

The model correctly predicted pro_longevity for cth-2. The mechanistic reasoning is well-grounded: cystathionine gamma-lyase produces H₂S via the transsulfuration pathway, and H₂S has documented pro-longevity effects in C. elegans and other organisms. The model correctly identifies PLP-dependent enzymatic mechanism, links to DAF-16/FOXO and SKN-1 pathways, and connects to antioxidant defense via glutathione biosynthesis. Confidence of 0.72 is appropriate given the gene is a "putative" CSE. The reasoning is solid and biologically accurate.

Raw API responses

solver

{
  "reasoning": "Cystathionine gamma-lyase (CSE) catalyzes the transsulfuration pathway step converting cystathionine to cysteine, and is a major enzymatic source of hydrogen sulfide (H₂S) in many organisms. H₂S is a gasotransmitter with well-established cytoprotective and pro-longevity effects: it activates stress-response pathways (including DAF-16/FOXO and Nrf2/SKN-1), enhances mitochondrial function at low concentrations, and reduces oxidative damage. In C. elegans, the transsulfuration pathway feeds into cysteine and glutathione biosynthesis, supporting antioxidant capacity and proteostasis. Pyridoxal phosphate (PLP) binding confirms the canonical enzymatic mechanism of this PLP-dependent lyase. Increased H₂S production via CSE activity has been linked to lifespan extension in multiple model organisms, including nematodes.",
  "confidence": 0.72,
  "key_pathways": [
    "transsulfuration pathway / hydrogen sulfide production",
    "glutathione biosynthesis and antioxidant defense",
    "DAF-16/FOXO stress response signaling"
  ],
  "mechanism_class": "other",
  "longevity_influence": "pro_longevity"
}

advisor

{
  "notes": "The model correctly predicted pro_longevity for cth-2. The mechanistic reasoning is well-grounded: cystathionine gamma-lyase produces H₂S via the transsulfuration pathway, and H₂S has documented pro-longevity effects in C. elegans and other organisms. The model correctly identifies PLP-dependent enzymatic mechanism, links to DAF-16/FOXO and SKN-1 pathways, and connects to antioxidant defense via glutathione biosynthesis. Confidence of 0.72 is appropriate given the gene is a \"putative\" CSE. The reasoning is solid and biologically accurate.",
  "failure_mode": "correct",
  "answer_correct": true,
  "mechanism_correct": true,
  "reasoning_quality": 4,
  "ground_truth_questionable": false
}