TOS8
S. cerevisiae
Tos8p
What the model saw
Gene: TOS8 Organism: Saccharomyces cerevisiae Known functions: Tos8p. DNA binding. DNA-binding transcription repressor activity, RNA polymerase II-specific. RNA polymerase II cis-regulatory region sequence-specific DNA binding. chromatin binding.
View unredacted entry
Tos8p. DNA binding. DNA-binding transcription repressor activity, RNA polymerase II-specific. RNA polymerase II cis-regulatory region sequence-specific DNA binding. chromatin binding.
Solver output
TOS8 encodes a homeodomain-containing transcription repressor that binds chromatin and cis-regulatory regions to silence RNA Pol II-dependent gene expression. In yeast, transcriptional repressors that bind chromatin often help maintain proper gene expression programs by silencing pro-aging or stress-response genes; loss of such repressors can lead to derepression of genes that accelerate aging. TOS8 has been identified as a repressor of genes involved in cell cycle progression and stress responses, and its chromatin-binding activity suggests a role in maintaining epigenetic gene silencing. Transcriptional repressors that preserve chromatin organization and suppress aberrant transcription are generally associated with pro-longevity effects, as dysregulation of chromatin-based silencing is a hallmark of epigenetic alterations in aging. The moderate confidence reflects that the specific targets of TOS8 repression are not fully characterized, leaving some uncertainty about net longevity impact.
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 pro_longevity but the ground truth is anti_longevity. The model's reasoning is based on a general heuristic that transcriptional repressors maintaining chromatin silencing tend to be pro-longevity, but this logic is flawed in this case. TOS8 is actually anti-longevity, meaning its presence shortens lifespan (i.e., deletion of TOS8 extends lifespan). The model's mechanistic reasoning about chromatin silencing and epigenetic maintenance being pro-longevity is a plausible general argument but does not apply here. The model showed moderate confidence (0.55) but still got both the answer and the mechanism wrong. The reasoning quality is low because it relied on overly generic heuristics without considering that TOS8 as a repressor could be suppressing pro-longevity genes, which would make it anti-longevity.
Raw API responses
solver
{
"reasoning": "TOS8 encodes a homeodomain-containing transcription repressor that binds chromatin and cis-regulatory regions to silence RNA Pol II-dependent gene expression. In yeast, transcriptional repressors that bind chromatin often help maintain proper gene expression programs by silencing pro-aging or stress-response genes; loss of such repressors can lead to derepression of genes that accelerate aging. TOS8 has been identified as a repressor of genes involved in cell cycle progression and stress responses, and its chromatin-binding activity suggests a role in maintaining epigenetic gene silencing. Transcriptional repressors that preserve chromatin organization and suppress aberrant transcription are generally associated with pro-longevity effects, as dysregulation of chromatin-based silencing is a hallmark of epigenetic alterations in aging. The moderate confidence reflects that the specific targets of TOS8 repression are not fully characterized, leaving some uncertainty about net longevity impact.",
"confidence": 0.55,
"key_pathways": [
"chromatin-based transcriptional silencing",
"RNA Pol II transcriptional repression",
"epigenetic gene regulation"
],
"mechanism_class": "epigenetic_alterations",
"longevity_influence": "pro_longevity"
}advisor
{
"notes": "The model predicted pro_longevity but the ground truth is anti_longevity. The model's reasoning is based on a general heuristic that transcriptional repressors maintaining chromatin silencing tend to be pro-longevity, but this logic is flawed in this case. TOS8 is actually anti-longevity, meaning its presence shortens lifespan (i.e., deletion of TOS8 extends lifespan). The model's mechanistic reasoning about chromatin silencing and epigenetic maintenance being pro-longevity is a plausible general argument but does not apply here. The model showed moderate confidence (0.55) but still got both the answer and the mechanism wrong. The reasoning quality is low because it relied on overly generic heuristics without considering that TOS8 as a repressor could be suppressing pro-longevity genes, which would make it anti-longevity.",
"failure_mode": "confident_wrong",
"answer_correct": false,
"mechanism_correct": false,
"reasoning_quality": 2,
"ground_truth_questionable": false
}