ISW2
S. cerevisiae
DNA translocase
What the model saw
Gene: ISW2 Organism: Saccharomyces cerevisiae Known functions: DNA translocase. ATP binding. DNA binding. DNA translocase activity. centromeric DNA binding. chromatin binding. nucleosome array spacer activity. nucleosome binding. protein binding. single-stranded DNA binding.
View unredacted entry
DNA translocase. ATP binding. DNA binding. DNA translocase activity. centromeric DNA binding. chromatin binding. nucleosome array spacer activity. nucleosome binding. protein binding. single-stranded DNA binding.
Solver output
ISW2 encodes the catalytic ATPase subunit of the ISW2 chromatin remodeling complex in S. cerevisiae, which uses ATP-dependent DNA translocase activity to reposition and space nucleosome arrays. Proper nucleosome spacing and chromatin organization are essential for maintaining repressive chromatin states, particularly at subtelomeric and repetitive regions, thereby suppressing cryptic transcription and preserving epigenetic silencing. Loss of ISW2-mediated nucleosome spacing leads to derepression of genes and increased genomic instability, both of which are associated with accelerated aging. Chromatin remodelers that maintain ordered nucleosome arrays help preserve the epigenetic landscape that erodes with age, a hallmark of aging in yeast and other organisms. Additionally, ISW2 has been linked to repression of stress-response and metabolic genes, and its activity at centromeric DNA may contribute to chromosomal stability during replication.
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 ISW2 as pro_longevity, but the ground truth is anti_longevity. The model's reasoning argued that ISW2 maintains repressive chromatin states and nucleosome spacing, which would be beneficial for longevity. However, the actual finding is that ISW2 is anti-longevity, meaning its deletion or loss extends lifespan. This is consistent with research showing that ISW2 represses stress-response genes and that its deletion can extend replicative lifespan in yeast. The model's mechanistic reasoning was essentially inverted — it correctly identified ISW2's role in chromatin remodeling and nucleosome spacing but drew the wrong conclusion about the direction of its effect on longevity. The model had moderate confidence (0.65) but was still clearly wrong. The reasoning quality is low because the model failed to consider that repression of stress-response genes by ISW2 could be detrimental to longevity, and that loss of ISW2 (anti_longevity gene) would extend lifespan by derepressing those pathways.
Raw API responses
solver
{
"reasoning": "ISW2 encodes the catalytic ATPase subunit of the ISW2 chromatin remodeling complex in S. cerevisiae, which uses ATP-dependent DNA translocase activity to reposition and space nucleosome arrays. Proper nucleosome spacing and chromatin organization are essential for maintaining repressive chromatin states, particularly at subtelomeric and repetitive regions, thereby suppressing cryptic transcription and preserving epigenetic silencing. Loss of ISW2-mediated nucleosome spacing leads to derepression of genes and increased genomic instability, both of which are associated with accelerated aging. Chromatin remodelers that maintain ordered nucleosome arrays help preserve the epigenetic landscape that erodes with age, a hallmark of aging in yeast and other organisms. Additionally, ISW2 has been linked to repression of stress-response and metabolic genes, and its activity at centromeric DNA may contribute to chromosomal stability during replication.",
"confidence": 0.65,
"key_pathways": [
"ATP-dependent chromatin remodeling / nucleosome spacing",
"epigenetic silencing maintenance",
"centromeric chromatin organization"
],
"mechanism_class": "epigenetic_alterations",
"longevity_influence": "pro_longevity"
}advisor
{
"notes": "The model predicted ISW2 as pro_longevity, but the ground truth is anti_longevity. The model's reasoning argued that ISW2 maintains repressive chromatin states and nucleosome spacing, which would be beneficial for longevity. However, the actual finding is that ISW2 is anti-longevity, meaning its deletion or loss extends lifespan. This is consistent with research showing that ISW2 represses stress-response genes and that its deletion can extend replicative lifespan in yeast. The model's mechanistic reasoning was essentially inverted — it correctly identified ISW2's role in chromatin remodeling and nucleosome spacing but drew the wrong conclusion about the direction of its effect on longevity. The model had moderate confidence (0.65) but was still clearly wrong. The reasoning quality is low because the model failed to consider that repression of stress-response genes by ISW2 could be detrimental to longevity, and that loss of ISW2 (anti_longevity gene) would extend lifespan by derepressing those pathways.",
"failure_mode": "confident_wrong",
"answer_correct": false,
"mechanism_correct": false,
"reasoning_quality": 2,
"ground_truth_questionable": false
}