cbs-1
C. elegans
Cystathionine beta-synthase cbs-1
What the model saw
Gene: cbs-1 Organism: Caenorhabditis elegans Known functions: Cystathionine beta-synthase cbs-1. cystathionine beta-synthase activity. cysteine synthase activity. heme binding. pyridoxal phosphate binding.
View unredacted entry
Cystathionine beta-synthase cbs-1. cystathionine beta-synthase activity. cysteine synthase activity. heme binding. pyridoxal phosphate binding.
Solver output
CBS-1 is the C. elegans cystathionine beta-synthase, which catalyzes the first committed step of the transsulfuration pathway, converting homocysteine and serine to cystathionine. This pathway is the primary endogenous source of hydrogen sulfide (H₂S), a gasotransmitter with well-documented pro-longevity effects in C. elegans and other organisms. H₂S produced via transsulfuration activates stress-resistance pathways (including DAF-16/FOXO and SKN-1/Nrf2), reduces mitochondrial oxidative stress, and has been shown to extend lifespan in worms. Additionally, the transsulfuration pathway feeds into cysteine and glutathione biosynthesis, bolstering antioxidant defenses and proteostasis. The pyridoxal phosphate (PLP) and heme cofactor dependencies are consistent with canonical CBS enzymatic function, reinforcing that this gene's primary role is H₂S and cysteine production rather than an unrelated process.
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 predicted pro_longevity for cbs-1. The mechanistic reasoning is detailed and accurate: CBS-1 catalyzes the transsulfuration pathway producing H₂S, which has well-documented pro-longevity effects in C. elegans. The model correctly identifies downstream pathways (DAF-16/FOXO, SKN-1/Nrf2, glutathione biosynthesis) and the cofactor dependencies (PLP, heme) consistent with CBS function. Confidence of 0.75 is appropriate given the specificity of the evidence. Overall, this is an excellent prediction with sound mechanistic reasoning.
Raw API responses
solver
{
"reasoning": "CBS-1 is the C. elegans cystathionine beta-synthase, which catalyzes the first committed step of the transsulfuration pathway, converting homocysteine and serine to cystathionine. This pathway is the primary endogenous source of hydrogen sulfide (H₂S), a gasotransmitter with well-documented pro-longevity effects in C. elegans and other organisms. H₂S produced via transsulfuration activates stress-resistance pathways (including DAF-16/FOXO and SKN-1/Nrf2), reduces mitochondrial oxidative stress, and has been shown to extend lifespan in worms. Additionally, the transsulfuration pathway feeds into cysteine and glutathione biosynthesis, bolstering antioxidant defenses and proteostasis. The pyridoxal phosphate (PLP) and heme cofactor dependencies are consistent with canonical CBS enzymatic function, reinforcing that this gene's primary role is H₂S and cysteine production rather than an unrelated process.",
"confidence": 0.75,
"key_pathways": [
"transsulfuration pathway / H2S production",
"glutathione biosynthesis and antioxidant defense",
"DAF-16/FOXO and SKN-1/Nrf2 stress-resistance signaling"
],
"mechanism_class": "other",
"longevity_influence": "pro_longevity"
}advisor
{
"notes": "The model correctly predicted pro_longevity for cbs-1. The mechanistic reasoning is detailed and accurate: CBS-1 catalyzes the transsulfuration pathway producing H₂S, which has well-documented pro-longevity effects in C. elegans. The model correctly identifies downstream pathways (DAF-16/FOXO, SKN-1/Nrf2, glutathione biosynthesis) and the cofactor dependencies (PLP, heme) consistent with CBS function. Confidence of 0.75 is appropriate given the specificity of the evidence. Overall, this is an excellent prediction with sound mechanistic reasoning.",
"failure_mode": "correct",
"answer_correct": true,
"mechanism_correct": true,
"reasoning_quality": 5,
"ground_truth_questionable": false
}