FCY21
S. cerevisiae
purine-cytosine permease
What the model saw
Gene: FCY21 Organism: Saccharomyces cerevisiae Known functions: purine-cytosine permease. nucleobase transmembrane transporter activity. transmembrane transporter activity.
View unredacted entry
purine-cytosine permease. nucleobase transmembrane transporter activity. transmembrane transporter activity.
Solver output
FCY21 encodes a purine-cytosine permease responsible for transmembrane transport of nucleobases (purines and cytosine) into yeast cells. While nucleobase salvage pathways can influence nucleotide pools and thereby affect DNA replication fidelity and repair capacity, the direct connection of this specific transporter to longevity-relevant pathways is not well established. Nucleobase transport could theoretically support nucleotide homeostasis (relevant to genomic stability) or feed into purine-sensing pathways that intersect with TORC1 nutrient sensing, but neither direction is strongly supported by the available annotations alone. The function is too peripheral and context-dependent to confidently assign a pro- or anti-longevity role.
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 was appropriately uncertain given the limited functional annotations, but it failed to arrive at the correct answer. The mechanistic reasoning about nucleobase transport potentially intersecting with TORC1 nutrient sensing is speculative and not well-grounded. The model correctly identified the gene's function as a purine-cytosine permease but couldn't connect it to a longevity direction. Since FCY21 is anti-longevity (meaning its deletion extends lifespan), the model missed this classification entirely. The reasoning quality is low-moderate — it's cautious but doesn't provide useful mechanistic insight into why this transporter would be anti-longevity.
Raw API responses
solver
{
"reasoning": "FCY21 encodes a purine-cytosine permease responsible for transmembrane transport of nucleobases (purines and cytosine) into yeast cells. While nucleobase salvage pathways can influence nucleotide pools and thereby affect DNA replication fidelity and repair capacity, the direct connection of this specific transporter to longevity-relevant pathways is not well established. Nucleobase transport could theoretically support nucleotide homeostasis (relevant to genomic stability) or feed into purine-sensing pathways that intersect with TORC1 nutrient sensing, but neither direction is strongly supported by the available annotations alone. The function is too peripheral and context-dependent to confidently assign a pro- or anti-longevity role.",
"confidence": 0.35,
"key_pathways": [
"nucleobase salvage pathway",
"purine/pyrimidine transport",
"nucleotide pool homeostasis"
],
"mechanism_class": "deregulated_nutrient_sensing",
"longevity_influence": "unclear"
}advisor
{
"notes": "The model predicted \"unclear\" while the ground truth is \"anti_longevity.\" The model was appropriately uncertain given the limited functional annotations, but it failed to arrive at the correct answer. The mechanistic reasoning about nucleobase transport potentially intersecting with TORC1 nutrient sensing is speculative and not well-grounded. The model correctly identified the gene's function as a purine-cytosine permease but couldn't connect it to a longevity direction. Since FCY21 is anti-longevity (meaning its deletion extends lifespan), the model missed this classification entirely. The reasoning quality is low-moderate — it's cautious but doesn't provide useful mechanistic insight into why this transporter would be anti-longevity.",
"failure_mode": "appropriately_uncertain",
"answer_correct": false,
"mechanism_correct": false,
"reasoning_quality": 2,
"ground_truth_questionable": false
}