The FADS1 HRP-conjugated antibody is a recombinant monoclonal or polyclonal antibody chemically linked to HRP, an enzyme used for signal amplification in assays like Western blot (WB) and ELISA. Key structural and functional attributes include:
FADS1 HRP-conjugated antibodies are widely used to study lipid metabolism and disease mechanisms:
Western Blot: Detects FADS1 at 2.5 µg/mL with secondary antibody dilutions of 1:50,000–100,000 .
ELISA: Effective at 1:312,500 dilution for quantitative analysis .
Functional Studies: Used to validate FADS1 overexpression in hepatocytes, demonstrating its role in improving glucose metabolism and reducing hepatic lipid accumulation .
Genetic Regulation: Identifies allele-specific FADS1 expression modulated by transcription factors like PATZ1 and SREBP1c .
Hepatocyte-specific FADS1 overexpression in rats fed a high-fat diet restored arachidonic acid (AA)/dihomo-γ-linolenic acid (DGLA) ratios, mitigating insulin resistance and hepatic lipidosis . This highlights FADS1's therapeutic potential for metabolic disorders.
The rs174557 SNP in the FADS1 promoter influences enhancer activity, with the D haplotype linked to higher FADS1 expression .
PATZ1 binds rs174557, suppressing FADS1 transcription and reducing AA synthesis .
FADS1 regulates phosphatidylinositol-4,5-bisphosphate levels in T-cells, modulating cytokine production and inflammation . Its dysregulation is implicated in breast cancer stem cell growth and ferroptosis sensitivity in gastric cancer .
Commercial FADS1 HRP antibodies are rigorously validated:
Activity Assays: AA/DGLA ratios confirm FADS1 enzymatic function in lipidomics .
Batch Consistency: Protein A/G purification ensures high reproducibility .
Isoform Variability: Isoform 2 lacks catalytic activity, necessitating isoform-specific antibodies .
Species Specificity: Some antibodies show limited reactivity in non-mammalian species .
Storage: Lyophilized antibodies require reconstitution in PBS with 0.02% sodium azide for long-term stability .
Recent studies underscore FADS1's role in metabolic and inflammatory pathways, positioning it as a target for therapies against MASLD, cardiovascular diseases, and cancer . Advanced lipidomics and CRISPR-based validation will further elucidate its mechanisms.
FADS1 functions as a front-end fatty acyl-coenzyme A (CoA) desaturase that catalyzes the conversion of dihomo-gamma-linoleoate (DGLA) (20:3n-6) to arachidonate (AA) (20:4n-6) and eicosatetraenoate (ETA) (20:4n-3) to eicosapentaenoate (EPA) (20:5n-3). As a rate-limiting enzyme in eicosanoid biosynthesis, FADS1 controls the metabolism of inflammatory lipids like prostaglandin E2, which is critical for efficient acute inflammatory response and maintenance of epithelium homeostasis. FADS1 also contributes significantly to membrane phospholipid biosynthesis by supplying AA as a major acyl chain component. Recent research indicates that FADS1 may be a promising therapeutic target for metabolic associated steatotic liver disease (MASLD) in a diet-dependent manner, highlighting its importance in metabolic research .
HRP-conjugated FADS1 antibodies are primarily optimized for techniques that rely on enzymatic detection systems. The major compatible techniques include:
| Technique | Compatibility | Dilution Range | Notes |
|---|---|---|---|
| Western Blot | Excellent | 1:1000-1:2000 | Direct detection without secondary antibody |
| ELISA | Excellent | 1:1000-1:5000 | Reduces protocol steps |
| Immunohistochemistry | Good | 1:100-1:500 | May require optimization for tissue type |
| Flow Cytometry | Limited | 1:50-1:200 | Better results with permeabilized cells |
The HRP conjugation eliminates the need for secondary antibody incubation, simplifying protocols and reducing background noise in many applications .
Validating antibody specificity is crucial for reliable research results. For HRP-conjugated FADS1 antibody, a multi-step validation approach is recommended:
Positive control tissues/cells known to express FADS1: Human liver samples or HepG2 cells show robust FADS1 expression as demonstrated in western blot analyses with bands at approximately 52 kDa (the predicted molecular weight of FADS1) .
Negative controls: Include samples from knockout models or use siRNA-mediated knockdown of FADS1 to confirm signal reduction.
Blocking peptide competition: Pre-incubate the antibody with the immunizing peptide to confirm signal abolishment.
Cross-reactivity assessment: Test the antibody in tissues where FADS1 expression should be minimal or absent.
Isoform specificity: Determine whether the antibody recognizes specific FADS1 isoforms. The EPR6898 clone detects isoform 1, which possesses catalytic activity, making it ideal for functional studies .
Optimizing Western blot protocols for HRP-conjugated FADS1 antibody in challenging samples requires careful consideration of several factors:
Sample preparation: For fatty tissues or those with high lipid content (common when studying FADS1), use a modified RIPA buffer containing 1% NP-40 and 0.1% SDS with additional protease inhibitors. Sonication followed by centrifugation at 14,000g for 15 minutes helps remove lipid interference.
Protein loading: Optimize protein loading (8-12 μg for cell lysates, 15-20 μg for tissue samples) to detect FADS1 without oversaturation.
Blocking: Use 5% BSA in TBST rather than milk, as milk proteins can interact with fatty acid-processing enzymes like FADS1.
Antibody dilution: Start with 1:1000 dilution and adjust based on signal strength. For weak signals, extend incubation to overnight at 4°C with gentle rocking.
Chemiluminescence substrate selection: High-sensitivity substrates may be needed for tissues with low FADS1 expression. Consider using femto-grade substrates for brain tissue samples where FADS1 expression is lower than in liver samples .
Interpreting the relationship between FADS1 expression and fatty acid profiles requires understanding the enzyme's functional activity beyond mere protein expression levels. Key considerations include:
AA/DGLA ratio: The arachidonic acid (AA, C20:4n6) to dihomo-γ-linolenic acid (DGLA, C20:3n6) ratio serves as a functional measurement of FADS1 activity. A reduced ratio indicates decreased FADS1 activity, regardless of protein expression levels. Lipidomics analysis has shown that in high-fat high-fructose (HFHFr) diet models, this ratio markedly decreases in phospholipid and total fatty acid pools, indicating impaired FADS1 function .
Compartment-specific effects: FADS1 activity affects different lipid compartments differently. Assess phospholipid, neutral lipid, and free fatty acid fractions separately.
Context-dependent activity: FADS1 expression and activity can be diet-dependent. For example, hepatocyte-specific FADS1 overexpression rescues the reduced AA/DGLA ratio in HFHFr-fed rats but shows differential effects in low-fat high-fructose (LFHFr) diets .
Downstream metabolite analysis: Beyond AA/DGLA ratio, examine eicosanoid profiles (prostaglandins, leukotrienes) to determine the functional impact of altered FADS1 expression or activity.
Pathway integration: Correlate FADS1 data with other desaturases (especially FADS2) and elongases to comprehensively understand fatty acid metabolism alterations.
Distinguishing between FADS1 isoforms requires specialized approaches since standard antibodies may not differentiate between isoforms. Consider these methodological strategies:
Isoform-specific antibodies: Use antibodies raised against unique epitopes. Isoform 1 has catalytic activity toward 20:3n-6, while isoform 2 lacks this activity but may enhance FADS2 function .
RT-PCR with isoform-specific primers: Design primers targeting unique regions of each isoform's mRNA to quantify relative expression.
Functional activity assays: The AA/DGLA ratio primarily reflects isoform 1 activity. Changes in this ratio without corresponding changes in FADS2 activity may help distinguish between isoforms.
Subcellular fractionation: Different isoforms may have distinct subcellular localizations. Western blot analysis of subcellular fractions using HRP-conjugated FADS1 antibody can reveal differential distribution patterns.
Mass spectrometry: Targeted proteomics can identify isoform-specific peptides, providing definitive identification and quantification.
When investigating FADS1's role in inflammation, consider these experimental design elements:
Cell/tissue selection: Choose models relevant to inflammation. FADS1 regulates phosphatidylinositol-4,5-bisphosphate levels, modulating inflammatory cytokine production in T-cells. Include both immune cells and target tissues in your experimental design .
Stimulation conditions: Establish appropriate inflammatory stimuli (LPS, TNF-α, IL-1β) and time points for acute vs. chronic inflammation models.
Pathway analysis: Measure both upstream fatty acid precursors and downstream inflammatory mediators:
Substrate levels: DGLA (20:3n-6) and ETA (20:4n-3)
Product levels: AA (20:4n-6) and EPA (20:5n-3)
Eicosanoids: Prostaglandin E2 and other inflammatory lipids
Cytokines: TNF-α, IL-6, IL-1β
Intervention approaches:
Readout systems:
Protein expression: Western blot with HRP-conjugated FADS1 antibody
Activity measurement: AA/DGLA ratio by lipidomics
Inflammatory markers: ELISA for cytokines, eicosanoid measurements
Functional outcomes: Cell migration, adhesion, or tissue-specific inflammation markers
Different tissues require specific controls and preparation methods when using HRP-conjugated FADS1 antibodies:
For all tissues, include:
Positive controls: HepG2 cells consistently show FADS1 expression
Negative controls: Primary antibody omission and isotype controls
Loading controls: β-actin or GAPDH to normalize expression data
Inconsistent results when measuring FADS1 expression and activity can stem from several sources. Use this troubleshooting guide to address common issues:
Discrepancy between protein expression and enzymatic activity:
FADS1 activity (AA/DGLA ratio) can be altered independently of protein expression levels
Post-translational modifications may affect enzyme function without changing expression
Solution: Always measure both protein levels (using HRP-conjugated FADS1 antibody) and enzymatic activity (AA/DGLA ratio by lipidomics)
Inconsistent Western blot results:
Protein degradation: Ensure proper sample handling and storage at -80°C
Insufficient blocking: Increase BSA concentration to 5% and extend blocking time
Antibody degradation: Aliquot antibody and avoid freeze-thaw cycles
Solution: Include positive controls (HepG2 lysates) and standardize protein loading (10-15 μg)
Variable AA/DGLA ratios:
Dietary influences: Standardize animal diets or account for dietary fatty acid intake
Extraction method variability: Use consistent lipid extraction protocols
Solution: Normalize to internal standards and use technical replicates
Inter-tissue variation:
Differentiating between genetic and dietary influences on FADS1 activity requires sophisticated experimental approaches:
Cross-sectional studies with dietary assessment:
Measure FADS1 protein expression using HRP-conjugated antibodies
Determine AA/DGLA ratios via lipidomics
Assess dietary fatty acid intake using validated questionnaires
Perform genotyping for known FADS1 polymorphisms
Statistical approach: Multiple regression analysis to parse genetic vs. dietary variance
Controlled dietary interventions:
Design: Pre-post measurement in subjects with known FADS1 genotypes
Control diet composition precisely, particularly LA (18:2n-6) and ALA (18:3n-3) intake
Measure FADS1 expression and AA/DGLA ratios before and after intervention
Analysis: ANOVA with genotype as between-subjects factor and diet as within-subjects factor
Animal models with genetic manipulation:
Utilize AAV8-mediated hepatocyte-specific FADS1 overexpression, as demonstrated in recent research
Test different diets (chow, HFHFr, LFHFr) with controlled genetic expression
Measure both FADS1 protein expression and activity (AA/DGLA ratio)
Analysis: Two-way ANOVA (genotype × diet) with appropriate post-hoc tests
Cell culture models:
Establish cells with varying FADS1 genotypes (wild-type, heterozygous, homozygous variants)
Expose to different fatty acid treatments mimicking dietary patterns
Measure FADS1 expression using the HRP-conjugated antibody and enzyme activity
Analysis: Factorial design with genotype and fatty acid treatment as factors
Multi-parameter imaging with HRP-conjugated FADS1 antibodies can reveal spatial relationships between FADS1 expression and other cellular components:
Sequential multiplex immunohistochemistry:
First detection: HRP-conjugated FADS1 antibody with DAB substrate (brown)
Antibody stripping: Glycine-SDS (pH 2.0) buffer to remove primary-secondary complexes
Subsequent markers: Other enzymes in fatty acid metabolism pathway with different chromogens
Analysis: Digital image analysis for co-localization and quantitative expression
Immunofluorescence multiplexing:
Convert HRP signal to fluorescence using tyramide signal amplification (TSA)
Combine with non-HRP conjugated antibodies against related proteins
Analysis: Confocal microscopy with spectral unmixing
Tissue-specific expression mapping:
Apply HRP-conjugated FADS1 antibody to tissue microarrays
Correlate expression with tissue metadata (disease state, patient characteristics)
Analysis: Machine learning algorithms for pattern recognition
Subcellular localization studies:
Combine with organelle markers (ER, mitochondria, Golgi)
Determine precise localization of FADS1 in different physiological states
Analysis: Super-resolution microscopy for nanoscale localization
When evaluating therapeutic interventions targeting fatty acid metabolism with FADS1 antibodies, consider these methodological approaches:
Baseline characterization:
Establish normal ranges for FADS1 expression in target tissues
Determine physiological AA/DGLA ratios in different lipid fractions
Map correlations between FADS1 expression and disease biomarkers
Intervention monitoring:
Serial sampling: Consider the half-life of FADS1 (approximately 48 hours) when designing sampling timepoints
Paired tissue-plasma analysis: Correlate tissue FADS1 expression with circulating fatty acid profiles
Functional readouts: Beyond AA/DGLA ratio, measure downstream inflammatory mediators
Hepatocyte-specific interventions:
Analytical validation:
Establish standard curves using recombinant FADS1 protein
Determine limits of detection and quantification for the HRP-conjugated antibody
Validate normalization strategies across different intervention groups
Outcome correlation:
Establish statistical models linking FADS1 expression/activity changes to clinical outcomes
Determine minimum biologically significant changes in FADS1 parameters
Account for confounding factors in intervention studies (age, sex, concurrent medications)
Research suggests that FADS1 is a promising therapeutic target for metabolic associated steatotic liver disease (MASLD) in a diet-dependent manner, highlighting the importance of dietary context in therapeutic interventions targeting this enzyme .