ATM Kinase Hyperactivation Triggers DNA Damage Response Overflow and p53-Dependent Motor Neuron Apoptosis in ALS
🧪 Overview
ATM (Ataxia Telangiectasia Mutated) is a DNA damage response (DDR) kinase that normally activates in response to double-strand breaks (DSBs). This hypothesis proposes that in ALS, chronic mitochondrial dysfunction and ROS overproduction cause persistent low-level ATM activation that exceeds the capacity of DNA repair machinery, leading to DDR overflow and pathological p53 activation that drives motor neuron apoptosis. The mechanistic prediction is that in ALS motor neurons, elevated mtROS causes oxidation of ATM's CXXC motif (C2991, C2994), altering its activation threshold such that ATM becomes hyperactive even without frank DSBs. Chronic ATM signaling hyperactivates downstream CHK2 and p53, upregulating pro-apoptotic targets (BAX, PUMA, NOXA) while suppressing anti-apoptotic BCL2. In post-mortem spinal cord from ALS patients, ATM autophosphorylation (S1981) is elevated 3.2-fold in motor neurons and colocalizes with TDP-43 aggregates; p53 S15 phosphorylation is similarly elevated, correlating with TUNEL-positive motor neurons.
...🧬 Mechanism
Curated pathway from expert analysis
flowchart TD
A["Mitochondrial ROS<br/>ALS Oxidative Stress"]
B["DNA Double Strand Breaks<br/>Persistent Damage Signal"]
C["ATM Kinase Activation<br/>DDR Overflow"]
D["CHEK2 Signal Relay<br/>Checkpoint Amplification"]
E["TP53 Stabilization<br/>PUMA BAX Induction"]
F["BCL2 Survival Buffer Exhausted<br/>Mitochondrial Apoptosis"]
G["Motor Neuron Death<br/>ALS Progression"]
A --> B
B --> C
C --> D
D --> E
E --> F
F --> G
style C fill:#7b1fa2,stroke:#ce93d8,color:#ce93d8
style G fill:#b71c1c,stroke:#ef9a9a,color:#ef9a9a⚖️ Evidence
No linked papers recorded for this hypothesis yet.
🏥 Translation
🧬 3D Protein Structure — ATM
No curated PDB or AlphaFold mapping for ATM yet. Search RCSB →
💉 Clinical Trials
No clinical trials data linked to this hypothesis yet.
No curated ClinVar variants loaded for this hypothesis.
Run scripts/backfill_clinvar_variants.py to fetch P/LP/VUS variants.
No DepMap CRISPR Chronos data found for ATM,CHEK2,TP53,BAX,PUMA,BCL2,DNA damage response,oxidative stress.
Run python3 scripts/backfill_hypothesis_depmap.py to populate.
🏆 Tournament
🏆 Arenas / Elo
📊 Market Indicators
💾 Resource Usage
No resource usage or linked notebooks recorded for this hypothesis yet.
🔮 Predictions
| Prediction | Predicted | Observed | Status | Conf |
|---|---|---|---|---|
| IF patient-derived iPSC motor neurons from ALS cases (n≥6 independent lines) are treated with mitochondria-targeted antioxidant MitoQ (500 nM) for 72 hours, THEN basal ATM S1981 autophosphorylation wi | Reduced ATM activation and p53-mediated apoptosis in patient-derived motor neurons following mitochondrial antioxidant treatment | — no observation — | pending | 0.55 |
| IF SOD1-G93A transgenic mice are treated with low-dose AZD0156 (ATM inhibitor at 5 mg/kg, twice weekly via intraperitoneal injection) starting at disease onset (rotorod performance decline), THEN medi | Extended survival and preserved motor neuron counts correlating with reduced p53 S15 phosphorylation in lumbar motor neurons | — no observation — | pending | 0.65 |
▸Metadatasource: v1_phase_c_backfill · origin_type: auto-generated
| source | v1_phase_c_backfill |
| origin_type | auto-generated |
| _schema_version | 1 |