J-protein substrate specificity codes enable HSP70 discrimination of β-sheet versus α-helical misfolded conformers
🧪 Overview
The HSP70 chaperone system achieves selective recognition of pathogenic protein conformers through a sophisticated client code mechanism where J-protein co-chaperones DNAJB6 and DNAJB2 exhibit distinct molecular recognition patterns for different misfolded structures. DNAJB6 contains specialized structural domains—serine/threonine-rich regions and glycine/phenylalanine repeats—that create a binding interface optimized for recognizing exposed β-sheet propensity sequences (5-15 residues) characteristic of amyloidogenic proteins. These cryptic hydrophobic stretches, normally buried in native protein cores, become accessible during pathological misfolding and present the specific 4.8 Å β-strand spacing that DNAJB6's architecture is evolved to detect. Upon recognition, DNAJB6 recruits HSPA8 or HSPA1A to form stable disaggregation complexes targeting amyloid cores and polyglutamine expansions. In contrast, DNAJB2 operates through fundamentally different binding kinetics, preferentially engaging α-helical intermediates and disordered regions typical of transiently misfolded native proteins.
...🧬 Mechanism
Curated pathway from expert analysis
flowchart TD
A["HSPA8, HSPA1A, DNAJB6, DNAJB2<br/>Hypothesis Target"]
B["Aggregation<br/>Cited Mechanism"]
C["Cellular Response<br/>Stress or Clearance Change"]
D["Neural Circuit Effect<br/>Synapse/Glia Vulnerability"]
E["Neurodegeneration<br/>Disease-Relevant Outcome"]
A --> B
B --> C
C --> D
D --> E
style A fill:#1a237e,stroke:#4fc3f7,color:#4fc3f7
style B fill:#b71c1c,stroke:#ef9a9a,color:#ef9a9a
style E fill:#b71c1c,stroke:#ef9a9a,color:#ef9a9a⚖️ Evidence
No linked papers recorded for this hypothesis yet.
🏥 Translation
🧬 3D Protein Structure — DNAJB6
No curated PDB or AlphaFold mapping for DNAJB6 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 DNAJB6.
Run python3 scripts/backfill_hypothesis_depmap.py to populate.
🏆 Tournament
🏆 Arenas / Elo
📊 Market Indicators
💾 Resource Usage
▸Metadatasource: v1_phase_c_backfill · origin_type: debate_synthesizer
| source | v1_phase_c_backfill |
| origin_type | debate_synthesizer |
| _schema_version | 1 |