TIA1 Low-Complexity Domain Oxidation Drives Aberrant Stress Granule Assembly and TDP-43 Mislocalization in ALS Motor Neurons
🧪 Overview
TIA1 (TIA-1) is an essential stress granule (SG) nucleator that undergoes oxidation-sensitive conformational changes in its low-complexity (LC) domain, modulating SG assembly dynamics. This hypothesis proposes that in ALS motor neurons, chronic oxidative stress (elevated ROS, mitochondrial dysfunction) causes irreversible oxidation of TIA1's LC domain cysteines, locking TIA1 into a hyper-assembly state that nucleates aberrant, gel-like SGs with altered material properties. These oxidized TIA1-SGs become detergent-insoluble, recruit TDP-43 through liquid-liquid phase separation (LLPS) co-partitioning, and seed cytoplasmic TDP-43 aggregation. The mechanistic prediction is that TIA1 LC domain oxidation (C37, C54, C71) creates a conformational lock that bypasses normal SG disassembly kinetics, producing pathological SG intermediates that resist autophagy clearance. In post-mortem spinal cord motor neurons from sporadic ALS patients, TIA1 shows increased oxidative modification (methionine sulfoxide, cysteine sulfinic acid) and colocalizes with TDP-43 aggregates in 73% of cases (Geser et al., 2011).
...🧬 Mechanism
Curated pathway from expert analysis
flowchart TD
A["Mitochondrial ROS<br/>ALS Oxidative Stress"]
B["TIA1 Low Complexity Domain Oxidation<br/>Stress Granule Nucleator Locked"]
C["Gel Like Stress Granules<br/>Reduced Dynamic Exchange"]
D["TDP43 Recruitment and Mislocalization<br/>Cytoplasmic RBP Sink"]
E["RNA Translation Arrest<br/>Repair mRNA Sequestration"]
F["Persistent Granule Pathology<br/>Proteostasis Failure"]
G["Motor Neuron Degeneration<br/>ALS Progression"]
A --> B
B --> C
C --> D
C --> E
D --> F
E --> G
F --> G
style B 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 — TIA1
No curated PDB or AlphaFold mapping for TIA1 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 TIA1,TDP-43,TARDBP,G3BP1,MAPK1,Oxidative stress response.
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 motor neuron-specific expression of TIA1-C37A/C54A/C71A (oxidation-resistant triple mutant) is induced in TDP-43 A315T transgenic mice using a Cre-lox system, THEN these mice will exhibit delayed o | Absence of cytoplasmic TDP-43 aggregates in lumbar spinal cord motor neurons at 6 months; preserved motor function on rotarod and grip strength tests; normal nu | — no observation — | pending | 0.65 |
| IF SOD1-G93A mice are treated with a CNS-penetrant TIA1 cysteine-reactive thiol-reducing compound (targeting oxidized C37/C54/C71 in the LC domain) for 12 consecutive weeks starting at disease onset, | ≥50% reduction in cytoplasmic TDP-43 mislocalization in ventral horn motor neurons; ≥30% improvement in rotarod performance; reduced detergent-insoluble TDP-43 | — no observation — | pending | 0.72 |
▸Metadatasource: v1_phase_c_backfill · origin_type: auto-generated
| source | v1_phase_c_backfill |
| origin_type | auto-generated |
| _schema_version | 1 |