STARD5 Antibody
Description
Target Protein Characteristics
STARD5 (UniProt ID: Q9H0Z9) is a 213-amino acid protein containing a conserved START domain that binds cholesterol and oxysterols. Key features:
| Property | Value/Description |
|---|---|
| Molecular Weight | 24 kDa |
| Tissue Expression | Liver > Kidney > Macrophages |
| Subcellular Location | Endoplasmic reticulum & plasma membrane |
| Key Ligands | Cholesterol, 25-hydroxycholesterol |
STARD5 regulates cholesterol distribution between cellular membranes and modulates lipid homeostasis through its sterol-binding capacity .
Antibody Applications in Recent Studies
STARD5 antibodies have enabled critical discoveries in metabolic research:
Table 1: Key Findings Using STARD5 Antibodies
These applications demonstrate the antibody's utility in detecting:
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Protein expression levels under dietary challenges
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Subcellular localization changes during ER stress
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Tissue-specific expression patterns
Technical Validation Data
Recent publications validate antibody performance:
Figure 1. Dose-dependent STARD5 Restoration (Ad-StarD5 MOI titration)
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MOI 10: 3.2× baseline expression
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MOI 50: 6.7× baseline expression
(Immunoblot quantification from primary hepatocyte studies)
Critical Validation Parameters:
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Specificity: No cross-reactivity with STARD4/6 in knockout controls
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Epitope Recognition: Confirmed via mass spec of immunoprecipitates
Disease Relevance Findings
STARD5 antibodies revealed pathological correlations:
Table 2: Clinical Correlations in Metabolic Disease
| Parameter | StarD5 −/− vs WT | Rescue Effect |
|---|---|---|
| HOMA-IR Score | 5.8 vs 2.1 (+176%) | Reduced to 3.2 (-45%) |
| Hepatic Cholesterol | 58 vs 34 mg/g (+70%) | 42 mg/g (-28%) |
| Plasma VLDL | 22 vs 40 mg/dL (-45%) | 35 mg/dL (+59%) |
| Fibrosis Stage | 2.3 vs 0.8 (ND) | Not reversed |
Data from WD-fed murine models demonstrates STARD5's role in lipid regulation and disease progression .
Research Limitations
Current antibody limitations:
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Limited multiplex compatibility in FFPE tissues
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No validated phospho-specific variants available
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Cross-reactivity with murine STARD5 only (non-human primate data lacking)
Recent advances include CRISPR-validated monoclonal antibodies showing improved signal-to-noise ratios in hepatic steatosis models .
Future Directions
Emerging applications:
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High-content screening for lipid-modifying therapeutics
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Single-cell resolution mapping in fibrotic niches
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Companion diagnostics for MASLD/MASH clinical trials
Product Specs
Target Background
Research suggests that STARD5, along with its counterparts StarD4 and StarD6, share a similar lipid binding pocket, particularly for sterols, but differ in their regulation and localization.
- Studies have shown that StarD4 is regulated by sterols through SREBP-2, while StarD5 is activated by ER stress and cholesterol metabolism, suggesting distinct roles for these proteins. (PMID: 24440759, PMID: 15760897)
- The presence of StarD5 exclusively in liver cytosolic fractions suggests its function as a directional cytosolic sterol carrier. (PMID: 15897605)
- The presence of StarD5 in various human liver cells related to inflammatory processes suggests a role in free sterol transport within these cells and in lipid-mediated atherogenesis. (PMID: 16534142)
- Data supports STARD5 functioning in the kidney, specifically within proximal tubule cells, and suggests a role in ER-associated cholesterol transport. (PMID: 19474188)
