Recombinant Pan troglodytes Interferon alpha-inducible protein 6 (IFI6)
Description
Definition and General Overview of IFI6
IFI6 (also known as G1P3, ISG16, or IFI6-16) is a 13–16 kDa protein induced by type I interferons (IFN-α/β) and other innate immune stimuli . It is evolutionarily conserved across mammals, with orthologs identified in primates, rodents, and other species . IFI6 plays dual roles in immunomodulation and antiviral defense, though its precise molecular mechanisms remain under investigation .
Key Functions of IFI6:
Molecular and Functional Characteristics
Human IFI6 is localized to the endoplasmic reticulum and nucleus , where it interacts with viral RNA or DNA to modulate replication. For example:
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HBV Suppression: Binds EnhII/Cp promoter (1715–1770 nt) to inhibit transcription .
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Flavivirus Inhibition: Prevents ER membrane invaginations critical for replication .
Experimental Models and Techniques
Recombinant human IFI6 has been engineered using plasmid systems (e.g., pCAGGS-IFI6-HA) for in vitro and in vivo studies . Key approaches include:
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Knockout/Knockdown: CRISPR-Cas9 or siRNA to study loss-of-function effects .
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Hydrodynamic Injection: Delivering IFI6 plasmids into mice to assess in vivo antiviral efficacy .
Potential Applications for Recombinant Pan troglodytes IFI6
While no data exist for Pan troglodytes IFI6, extrapolation from human studies suggests potential uses:
Lack of Pan troglodytes-Specific Data
No studies have characterized:
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Sequence Conservation: Alignment of Pan troglodytes IFI6 with human/primate orthologs.
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Functional Redundancy: Whether chimpanzee IFI6 retains antiviral or apoptotic roles observed in humans.
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Recombinant Engineering: Expression systems (e.g., bacterial, mammalian) for producing Pan troglodytes IFI6.
Technical Challenges
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RNA-Binding Specificity: Does Pan troglodytes IFI6 target viral RNA/DNA with the same affinity as human IFI6?
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Cross-Species Activity: Efficacy of Pan troglodytes IFI6 in human or non-primate models.
Product Specs
Note: We prioritize shipping the format currently in stock. However, if you have specific format requirements, please indicate them during order placement. We will prepare accordingly.
Note: All our proteins are shipped with standard blue ice packs. If dry ice shipping is required, please inform us in advance. Additional fees will apply.
Generally, the shelf life of liquid form is 6 months at -20°C/-80°C. The shelf life of lyophilized form is 12 months at -20°C/-80°C.
Target Background
Q&A
What experimental models are most effective for studying IFI6's dual role in antiviral defense and immune regulation?
Recombinant IFI6 studies typically employ cellular models (e.g., A549, BEAS-2B, 293T, HAP-1) for in vitro assays to evaluate its interaction with viral components or host proteins like RIG-I . For in vivo validation, murine models or humanized systems (e.g., liver chimeric mice) are critical to assess antiviral efficacy and immune modulation .
Key methodologies:
| Model | Application | Advantages | Limitations |
|---|---|---|---|
| Cell lines (A549) | RT-qPCR, viral replication assays | High throughput, reproducibility | Limited to acute infection dynamics |
| Murine models | In vivo IFI6 knockout studies | Mimics systemic immune response | Species-specific IFI6 expression may vary |
| Viral entry assays | Poly(I:C) transfection, rVSV-GFP infection | Measures innate immune activation | Overexpression artifacts may skew results |
How can researchers validate IFI6's RNA-binding ability in viral replication contexts?
IFI6’s RNA-binding capacity is hypothesized to modulate RIG-I activation . Validation requires:
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Co-immunoprecipitation (Co-IP): Identify IFI6-RNA complexes using tagged IFI6 constructs.
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Fluorescence microscopy: Track colocalization of IFI6 with viral RNA or ER-associated structures (e.g., double-membrane vesicles in flavivirus-infected cells) .
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RNA interference (RNAi): Knockdown IFI6 and assess RIG-I activation via phospho-IRF3 assays .
What challenges arise when analyzing IFI6's conflicting roles in apoptosis and immune regulation?
IFI6 exhibits context-dependent functions:
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Anti-apoptotic: Blocks cytochrome c release and stabilizes mitochondrial membranes .
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Pro-apoptotic: Induces TNFSF10-mediated apoptosis in certain contexts .
Data reconciliation strategies:
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Cell-type specificity analysis: Compare IFI6 effects in immune cells (e.g., macrophages) vs. epithelial cells (e.g., A549).
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Kinetic studies: Time-course experiments to distinguish early antiviral vs. late apoptotic phases .
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Signaling pathway inhibitors: Use EGFR kinase inhibitors to dissect IFI6’s role in HCV entry vs. apoptosis .
How does IFI6's interaction with RIG-I influence innate immune responses during viral infections?
IFI6 binds RIG-I via RNA intermediates, preventing its activation and downstream IFN/ISG production . This mechanism is critical in:
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Reducing cytokine storms: IFI6 knockdown exacerbates IFN-λ1 and pro-inflammatory cytokine expression in IAV/SARS-CoV-2 infections .
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Viral replication control: IFI6 overexpression suppresses IAV and SARS-CoV-2 titers by limiting antiviral gene activation .
What bioinformatics tools are essential for predicting IFI6's structural interactions with viral components?
Key tools:
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Homology modeling: Predict IFI6’s 3D structure using templates like FAM14 family proteins.
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Protein-RNA docking: Tools like HDOCK or Rosetta to simulate IFI6-RNA binding .
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Phylogenetic analysis: Compare IFI6 orthologs (e.g., chicken IFI6 ) to identify conserved RNA-binding motifs.
How to design experiments to study IFI6's species-specific effects on avian reovirus (ARV)?
Avian IFI6’s role in ARV replication requires:
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Cloning and overexpression: Use avian cell lines (e.g., ESCC) to express recombinant IFI6 .
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Subcellular localization: Fluorescent tagging to confirm ER localization and interaction with viral replication compartments .
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Viral titration: Quantify ARV replication in IFI6 knockdown vs. control cells .
What methodological limitations exist when using recombinant IFI6 in in vitro vs. in vivo systems?
| System | Strengths | Weaknesses |
|---|---|---|
| In vitro | Controlled environment, high reproducibility | Lack of physiological complexity |
| In vivo | Mimics systemic immune responses | Species-specific IFI6 expression challenges |
How to analyze data contradictions between IFI6's antiviral and immune-regulatory functions?
Approach:
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Contextual analysis: Compare IFI6 effects in early (antiviral) vs. late (immune regulation) infection stages .
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Multi-omics integration: Combine transcriptomics (IFN/ISG expression) and metabolomics (reactive oxygen species) .
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Dose-response studies: Assess IFI6 concentration thresholds for antiviral vs. immunosuppressive effects .
What are the key considerations for studying IFI6 in non-human primates (e.g., Pan troglodytes)?
Critical factors:
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Ortholog identification: Confirm IFI6 sequence conservation between Pan troglodytes and model organisms .
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Tissue-specific expression: Profile IFI6 in respiratory vs. hepatic tissues during viral infections .
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Ethical constraints: Prioritize in vitro models (e.g., primary primate cells) over in vivo testing.
