car2
S. pombe
ornithine transaminase Car2
What the model saw
Gene: car2 Organism: Schizosaccharomyces pombe Known functions: ornithine transaminase Car2. L-ornithine transaminase activity. pyridoxal phosphate binding.
View unredacted entry
ornithine transaminase Car2. L-ornithine transaminase activity. pyridoxal phosphate binding.
Solver output
Car2 encodes ornithine transaminase (OAT), a pyridoxal phosphate-dependent enzyme that catalyzes the conversion of L-ornithine to glutamate-5-semialdehyde, feeding into proline biosynthesis and the urea cycle. In yeast, ornithine catabolism via OAT connects arginine/ornithine metabolism to nitrogen sensing pathways, including TOR signaling. Elevated OAT activity promotes nitrogen utilization and anabolic signaling, which is associated with reduced longevity in the context of nutrient-sensing deregulation. Loss-of-function mutations in ornithine transaminase have been linked to lifespan extension in yeast models by reducing nitrogen flux and dampening TOR pathway activity. Thus, the normal pro-catabolic/pro-anabolic function of Car2 is expected to oppose longevity by sustaining nutrient-sensing signals that antagonize stress resistance and autophagy.
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
The model correctly predicts anti_longevity for car2 in S. pombe. However, the mechanistic reasoning is speculative and not well-supported. The model invokes TOR signaling and nitrogen sensing as the primary mechanism, but there is no strong published evidence linking S. pombe car2 (ornithine transaminase) to TOR pathway regulation or lifespan extension via reduced nitrogen flux. The reasoning appears to be constructed post-hoc by connecting general yeast metabolism concepts rather than citing specific experimental evidence for car2 in S. pombe. The claim that "loss-of-function mutations in ornithine transaminase have been linked to lifespan extension in yeast models by reducing nitrogen flux and dampening TOR pathway activity" is presented with unwarranted specificity. The correct answer appears to be reached by reasonable inference about metabolic enzymes being anti-longevity, but the specific mechanistic pathway described is largely speculative.
Raw API responses
solver
{
"reasoning": "Car2 encodes ornithine transaminase (OAT), a pyridoxal phosphate-dependent enzyme that catalyzes the conversion of L-ornithine to glutamate-5-semialdehyde, feeding into proline biosynthesis and the urea cycle. In yeast, ornithine catabolism via OAT connects arginine/ornithine metabolism to nitrogen sensing pathways, including TOR signaling. Elevated OAT activity promotes nitrogen utilization and anabolic signaling, which is associated with reduced longevity in the context of nutrient-sensing deregulation. Loss-of-function mutations in ornithine transaminase have been linked to lifespan extension in yeast models by reducing nitrogen flux and dampening TOR pathway activity. Thus, the normal pro-catabolic/pro-anabolic function of Car2 is expected to oppose longevity by sustaining nutrient-sensing signals that antagonize stress resistance and autophagy.",
"confidence": 0.62,
"key_pathways": [
"ornithine/arginine catabolism",
"TOR nutrient sensing",
"nitrogen metabolism"
],
"mechanism_class": "deregulated_nutrient_sensing",
"longevity_influence": "anti_longevity"
}advisor
{
"notes": "The model correctly predicts anti_longevity for car2 in S. pombe. However, the mechanistic reasoning is speculative and not well-supported. The model invokes TOR signaling and nitrogen sensing as the primary mechanism, but there is no strong published evidence linking S. pombe car2 (ornithine transaminase) to TOR pathway regulation or lifespan extension via reduced nitrogen flux. The reasoning appears to be constructed post-hoc by connecting general yeast metabolism concepts rather than citing specific experimental evidence for car2 in S. pombe. The claim that \"loss-of-function mutations in ornithine transaminase have been linked to lifespan extension in yeast models by reducing nitrogen flux and dampening TOR pathway activity\" is presented with unwarranted specificity. The correct answer appears to be reached by reasonable inference about metabolic enzymes being anti-longevity, but the specific mechanistic pathway described is largely speculative.",
"failure_mode": "right_answer_wrong_reasoning",
"answer_correct": true,
"mechanism_correct": false,
"reasoning_quality": 2,
"ground_truth_questionable": false
}