acs-4
C. elegans
long-chain-fatty-acid--CoA ligase
What the model saw
Gene: acs-4 Organism: Caenorhabditis elegans Known functions: long-chain-fatty-acid--CoA ligase. long-chain fatty acid-CoA ligase activity.
View unredacted entry
long-chain-fatty-acid--CoA ligase. long-chain fatty acid-CoA ligase activity.
Solver output
ACS-4 encodes a long-chain fatty acid-CoA ligase (acyl-CoA synthetase), which catalyzes the activation of long-chain fatty acids to their acyl-CoA thioesters — the obligate first step for fatty acid entry into beta-oxidation, lipid synthesis, and membrane remodeling. In C. elegans, fatty acid metabolism is tightly coupled to nutrient-sensing pathways (e.g., DAF-2/insulin-IGF-1, AMPK, and mTOR), and the direction of longevity influence depends critically on which downstream fate the activated acyl-CoAs are channeled into. Increased flux through beta-oxidation can promote mitochondrial energy production and extend lifespan, while increased lipid anabolism or lipotoxic signaling can be detrimental. Because acs-4 is one of several partially redundant acyl-CoA synthetase paralogs in C. elegans and its specific metabolic context (anabolic vs. catabolic channeling) is not resolvable from molecular function annotations alone, the net longevity effect remains genuinely ambiguous. No strong prior evidence from the aging literature unambiguously assigns acs-4 to a pro- or anti-longevity role distinct from its paralogs.
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 predicted "unclear" while the ground truth is "anti_longevity." The model's reasoning is plausible in general terms about fatty acid metabolism but fails to identify the specific anti-longevity role of acs-4. The model correctly identifies the biochemical function (long-chain fatty acid-CoA ligase) but then hedges excessively, claiming the longevity effect is "genuinely ambiguous" and that no strong prior evidence assigns acs-4 a clear role. The confidence of 0.38 reflects appropriate uncertainty, but the model still got the answer wrong. The mechanistic reasoning about beta-oxidation vs. lipid anabolism is generic and doesn't capture why acs-4 specifically has an anti-longevity effect. This is a case of appropriate uncertainty leading to a wrong answer rather than confident wrongness.
Raw API responses
solver
{
"reasoning": "ACS-4 encodes a long-chain fatty acid-CoA ligase (acyl-CoA synthetase), which catalyzes the activation of long-chain fatty acids to their acyl-CoA thioesters — the obligate first step for fatty acid entry into beta-oxidation, lipid synthesis, and membrane remodeling. In C. elegans, fatty acid metabolism is tightly coupled to nutrient-sensing pathways (e.g., DAF-2/insulin-IGF-1, AMPK, and mTOR), and the direction of longevity influence depends critically on which downstream fate the activated acyl-CoAs are channeled into. Increased flux through beta-oxidation can promote mitochondrial energy production and extend lifespan, while increased lipid anabolism or lipotoxic signaling can be detrimental. Because acs-4 is one of several partially redundant acyl-CoA synthetase paralogs in C. elegans and its specific metabolic context (anabolic vs. catabolic channeling) is not resolvable from molecular function annotations alone, the net longevity effect remains genuinely ambiguous. No strong prior evidence from the aging literature unambiguously assigns acs-4 to a pro- or anti-longevity role distinct from its paralogs.",
"confidence": 0.38,
"key_pathways": [
"long-chain fatty acid activation (acyl-CoA synthesis)",
"fatty acid beta-oxidation",
"lipid anabolism and membrane remodeling"
],
"mechanism_class": "deregulated_nutrient_sensing",
"longevity_influence": "unclear"
}advisor
{
"notes": "The model predicted \"unclear\" while the ground truth is \"anti_longevity.\" The model's reasoning is plausible in general terms about fatty acid metabolism but fails to identify the specific anti-longevity role of acs-4. The model correctly identifies the biochemical function (long-chain fatty acid-CoA ligase) but then hedges excessively, claiming the longevity effect is \"genuinely ambiguous\" and that no strong prior evidence assigns acs-4 a clear role. The confidence of 0.38 reflects appropriate uncertainty, but the model still got the answer wrong. The mechanistic reasoning about beta-oxidation vs. lipid anabolism is generic and doesn't capture why acs-4 specifically has an anti-longevity effect. This is a case of appropriate uncertainty leading to a wrong answer rather than confident wrongness.",
"failure_mode": "appropriately_uncertain",
"answer_correct": false,
"mechanism_correct": false,
"reasoning_quality": 2,
"ground_truth_questionable": false
}