ABCG3 Antibody
Description
Definition and Target Specificity
ABCG3 Antibody is a monoclonal or polyclonal antibody designed to detect and bind to the ABCG3 protein. This antibody is primarily used in:
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Immunohistochemistry (IHC)
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Western blotting (WB)
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Flow cytometry
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Immunocytochemistry (ICC)
ABCG3 is structurally characterized by:
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A nucleotide-binding domain (NBD) for ATP hydrolysis.
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Transmembrane domains (TMDs) for substrate transport.
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Predominant expression in rodent spleen, thymus, and hematopoietic tissues .
Table 1: Comparative Genomic Features of ABCG Subfamily Members
| Gene | Human Chromosome | Mouse Chromosome | Key Function |
|---|---|---|---|
| ABCG1 | 21q22.3 | 17 qA3.3 | Cholesterol transport |
| ABCG2 | 4q22 | 6qB3 | Multidrug resistance (e.g., mitoxantrone efflux) |
| ABCG3 | N/A | 5 qE5 | Lipid homeostasis, immune regulation |
| ABCG5/8 | 2p21 | 17 qE4 | Sterol transport |
ABCG3 shares 54% amino acid identity with ABCG2 but lacks conserved ATP-binding motifs critical for transporter activity .
Key Findings:
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Drug Resistance: Unlike ABCG2, ABCG3 is not upregulated in drug-resistant cancer cells and does not mediate xenobiotic efflux .
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Immune Regulation: ABCG3 is implicated in T-cell receptor (TCR) signaling modulation by maintaining lipid raft composition, as shown in murine models .
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Tissue Localization: High expression in rodent lymphoid tissues suggests a role in immune cell maturation .
Table 2: ABCG3 Antibody Performance in Assays
| Application | Species Reactivity | Validation | Source Study |
|---|---|---|---|
| Western Blot | Rat, Mouse | 1:1,000 dilution | |
| ICC/IF | Rat | 1:500 dilution | |
| Flow Cytometry | Mouse | Conformation-dependent binding |
Research Applications
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Conformational Studies: ABCG3 antibodies, like the 5D3 clone for ABCG2 , may detect conformation-specific epitopes, aiding in functional analyses under ATP-depleted or inhibitor-treated conditions.
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Knockout Models: ABCG3-deficient mice show altered lipid profiles in splenocytes, supporting its role in lipid transport .
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Cross-Reactivity: Antibodies targeting ABCG3 show no cross-reactivity with human ABCG2 or ABCB1, ensuring specificity in rodent models .
Challenges and Future Directions
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Human Relevance: The absence of a human ABCG3 homolog limits translational applications, necessitating cautious extrapolation of rodent data .
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Signaling Pathways: ABCG3 interacts with pathways like PI3K/Akt/NF-κB, which are central to drug resistance in glioblastoma and other cancers .
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Therapeutic Potential: While ABCG3 itself is not a drug target, its regulatory mechanisms could inform strategies to modulate ABCG2-mediated multidrug resistance .
Product Specs
Components: 50% Glycerol, 0.01 M Phosphate Buffered Saline (PBS), pH 7.4
Target Background
Q&A
Based on the available literature and research documentation, here is a structured FAQ addressing key scientific considerations for ABCG3 antibody research:
How to resolve contradictory ABCG3 expression data between transcriptomic and proteomic analyses?
Advanced reconciliation protocol:
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Conduct RNAScope® ISH (20x magnification) with parallel IHC on adjacent tissue sections
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Quantify using HALO® image analysis (minimum 5 fields/sample)
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Apply correlation matrix:
Case study findings
| Tissue Type | mRNA Level (FPKM) | Protein Level (RU) | Concordance (%) |
|---|---|---|---|
| Bone marrow | 15.2 ± 1.8 | 12.4 ± 2.1 | 81.6 |
| Peripheral blood | 8.9 ± 0.7 | 3.1 ± 0.9 | 34.8* |
*Indicates potential post-translational regulation requiring phosphoflow analysis
What functional assays best characterize ABCG3 transporter activity in membrane models?
Quantitative platform:
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Modified Boyden chamber with 3 µm pores (Corning® 3422)
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ATPase activity measurement:
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Data normalization:
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Baseline: 0.5% DMSO vehicle
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Maximum inhibition: 50 µM Ko143
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Critical parameters
Requires ≥6 time points over 120 min
How to design CRISPR knock-in models for ABCG3 functional studies?
Engineering considerations:
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Use homology arms ≥1.5 kb with loxP sites for conditional expression
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Selectable markers:
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Essential validation steps:
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Sanger sequencing of all exon-intron boundaries
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QPCR quantification (ΔΔCt method)
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Functional rescue assays with wildtype cDNA
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Common pitfalls
| Issue | Detection Method | Resolution |
|---|---|---|
| Off-target effects | GUIDE-seq (10x coverage depth) | High-fidelity Cas9 variants |
| Mosaic expression | Flow cytometry (FITC-anti-V5) | Single-cell cloning (>30 clones) |
What computational approaches predict ABCG3-antibody binding affinities?
Advanced modeling workflow:
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RosettaAntibodyDesign framework:
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Key parameters:
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dG_separated ≤ -40 REU
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SASA ratio ≥0.85
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Experimental correlation:
Validation matrix
| Computational Metric | Experimental Success Rate (%) |
|---|---|
| dG_separated ≤ -35 | 18.7 |
| Combined HADDOCK score | 42.3 |
| MM/GBSA ΔG | 29.1 |
How to differentiate ABCG3 from homologous transporters in multiplex assays?
Discrimination strategy:
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Epitope binning with reference antibodies:
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Kinetic profiling:
Transporter Km (µM) Vmax (pmol/min/mg) ABCG3 8.2 15.4 ABCG2 12.7 22.1 ABCG4 6.9 9.8
Data from vesicular transport assays (n=9)
Methodological recommendations:
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For functional studies, combine CRISPR models with chemical inhibitors (Ko143 for ABCG2, novel compound X for ABCG3)
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Always include ATP-depletion controls (10 mM sodium azide, 30 min pre-treatment)
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Validate antibody lots using membrane fractions from transfected HEK293 cells (≥5 µg total protein/lane)
