The CINV2 antibody is a specialized research tool targeting cytosolic neutral invertase 2 (CINV2), an enzyme critical for sucrose metabolism in plants like Arabidopsis thaliana. This antibody enables precise detection and functional analysis of CINV2, which hydrolyzes sucrose into glucose and fructose to fuel cellular processes . While not commercially therapeutic, it serves as a vital reagent for studying carbon partitioning, root development, and metabolic feedback loops in plant systems .
| Parameter | Wild Type (WT) | cinv1/cinv2 Mutant |
|---|---|---|
| Root length (mm) | 65.2 ± 3.1 | 28.4 ± 2.7 |
| Neutral invertase activity (nmol/min/mg protein) | 50.8 ± 2.3 | 30.5 ± 0.7 |
| Glucose content (µmol/g FW) | 1.5 ± 0.2 | 0.48 ± 0.05 |
Mutants show stunted roots, collapsed cortical cells, and aberrant cell divisions in the stele . Exogenous glucose partially rescues root growth, confirming CINV2’s role in sustaining endogenous glucose pools .
CINV2 activity is modulated by:
Ethylene signaling: EIN3 transcriptionally represses PAP1, indirectly downregulating CINV1/2 .
Phospholipid interactions: PIP5K9 binds and inhibits CINV2, linking membrane dynamics to sucrose metabolism .
Feedback loops: Glucose stabilizes EIN3, creating a balance between growth and stress responses .
CINV2 (Cytosolic Invertase 2) is an enzyme involved in sugar transport and carbon metabolism pathways . It plays a critical role in plant physiology by catalyzing the hydrolysis of sucrose into glucose and fructose in the cytosol. The significance of CINV2 in research stems from its involvement in fundamental metabolic processes that affect plant growth, development, and response to environmental stresses. Antibodies against CINV2 are valuable tools for studying its expression, localization, and functional interactions in various experimental systems.
When validating a CINV2 antibody, researchers should implement multiple approaches:
Western blot analysis: Confirm specificity by detecting a band of the expected molecular weight (~63-68 kDa for CINV2)
Immunoprecipitation: Verify the antibody can capture native CINV2 protein
Immunofluorescence: Assess proper cytosolic localization pattern
Knockout/knockdown controls: Test antibody on samples lacking CINV2 expression
Cross-reactivity testing: Ensure the antibody doesn't recognize related invertase family members
Epitope mapping: Characterize the specific binding region
Specificity assessment requires a multi-platform approach:
| Technique | Control | Expected Result | Common Pitfalls |
|---|---|---|---|
| Western blot | CINV2 knockout/knockdown | Absence of band | Background bands from related invertases |
| Immunoprecipitation | Pre-immune serum | No CINV2 pulldown | Non-specific protein interactions |
| Immunohistochemistry | Blocking peptide | Signal reduction | Autofluorescence in plant tissues |
| Flow cytometry | Isotype control | No positive population | Cell permeabilization issues |
When working across species, validation must be performed separately for each organism due to potential epitope variations in CINV2 homologs.
CINV2 demonstrates tissue-specific expression patterns, with particularly high expression in metabolically active tissues. While the search results don't provide comprehensive expression data for CINV2 specifically, research indicates CINV2 is involved in sugar transport pathways and is found in phloem-adjacent tissues . When studying CINV2 expression:
Consider tissue-specific controls when quantifying expression levels
Account for developmental stages in your experimental design
Be aware that stress conditions can alter normal expression patterns
Use multiple detection methods (antibody-based western blot, RT-qPCR) to confirm expression profiles
To study CINV2 function effectively, consider these methodological approaches:
Genetic manipulation: CRISPR/Cas9-mediated knockout or RNAi-based knockdown to assess phenotypic changes
Protein interaction studies: Immunoprecipitation with CINV2 antibodies followed by mass spectrometry to identify binding partners
Metabolic analysis: Measure glucose/fructose levels in response to CINV2 perturbation
RNA silencing: Study transcriptional regulation of sugar transport pathways, as CINV2 has been implicated in phloem-restricted genetic processes
Subcellular localization: Immunofluorescence with CINV2 antibodies to track protein distribution
Recent advances in antibody development offer promising approaches for generating CINV2-specific antibodies:
Computational design: Fine-tuned RFdiffusion networks now enable de novo design of antibody variable domains that can bind to specific epitopes with atomic precision . This approach could be adapted to design antibodies targeting specific functional domains of CINV2.
Memory B-cell selection: Isolating memory B cells that produce potent antibodies, similar to approaches used in viral antibody development . This method focuses on selecting B cells that produce antibodies with desired binding characteristics.
Structure-guided epitope selection: Using structural data to identify unique, accessible regions of CINV2 that distinguish it from other invertase family members.
Phage display optimization: Incorporating negative selection steps against related invertases to enhance specificity.
The computational approach using fine-tuned RFdiffusion networks has demonstrated success in designing antibodies that bind user-specified epitopes with high accuracy, with cryo-EM validation showing near-identical binding to the design model .
Optimizing antibody affinity for detecting low-abundance CINV2 requires:
Affinity maturation techniques:
In vitro directed evolution through display technologies
Structure-guided mutation of complementarity-determining regions (CDRs)
Computational design to improve binding energetics
Signal amplification methods:
Tyramide signal amplification for immunohistochemistry
Proximity ligation assays for enhanced sensitivity
Polymerized reporter enzyme systems
Sample preparation optimization:
Enrichment of CINV2-containing fractions
Optimized extraction buffers to maintain protein integrity
Reduced non-specific binding through buffer optimization
When evaluating antibody binding, molecular docking predictions can assess interaction energies similar to approaches used in other antibody research . Key parameters to analyze include HADDOCK score, van der Waals energy, electrostatic energy, and desolvation energy .
For effective immunoprecipitation of CINV2 from plant tissues, follow these methodological guidelines:
Buffer optimization: Use extraction buffers containing 50mM Tris-HCl (pH 7.5), 150mM NaCl, 5mM EDTA, 0.1% Triton X-100, supplemented with protease inhibitors and 1% glycerol to stabilize CINV2.
Sample preparation:
Grind tissue in liquid nitrogen to prevent protein degradation
Maintain low temperature (4°C) throughout the procedure
Clarify lysates by centrifugation at 14,000×g for 15 minutes
Antibody binding:
Pre-clear lysate with Protein A/G beads
Incubate with CINV2 antibody (2-5μg) overnight at 4°C
Add fresh Protein A/G beads for 2-3 hours
Perform stringent washes (4-5 times) with decreasing salt concentrations
Controls: Include relevant controls similar to those used in AGO protein immunoprecipitation studies , such as:
Input sample before immunoprecipitation
IgG control antibody
Immunoprecipitation from CINV2 knockout tissue
Elution strategies: Gentle elution with peptide competition or more stringent SDS-based elution depending on downstream applications.
When facing cross-reactivity challenges:
| Issue | Potential Cause | Solution |
|---|---|---|
| Multiple bands on Western blot | Recognition of related invertases | Peptide competition assay; use monoclonal antibodies |
| Non-specific tissue staining | Secondary antibody issues | Include secondary-only controls; increase blocking |
| Unexpected cell compartment signals | Antibody binding to homologous proteins | Verify with subcellular fractionation; use knockout controls |
| Inconsistent results across species | Epitope variation | Sequence alignment to identify conserved regions; species-specific validation |
For critical applications, consider using multiple antibodies targeting different CINV2 epitopes to confirm findings, similar to approaches used in studying memory B-cell-derived antibodies .
When analyzing CINV2 antibody binding data:
Binding affinity metrics: Calculate and compare:
HADDOCK scores
Van der Waals energy
Electrostatic energy
Desolvation energy
Buried surface area
PRODIGY's ΔG predictions
These parameters have proven valuable in antibody binding analysis .
Statistical approaches:
Visualization methods:
Generate heat maps of binding energies across different epitopes
Create structural models highlighting interaction interfaces
Plot affinity distributions for different antibody clones
Correlation analysis: Assess relationships between computational predictions and experimental binding data, similar to correlations observed between in silico predictions and empirical IC50 values in antibody studies .
To differentiate between CINV2 isoforms:
Epitope mapping: Identify isoform-specific regions for targeted antibody development.
Western blot optimization:
Use high-resolution SDS-PAGE (8-10%)
Extend running time to separate closely migrating isoforms
Consider using Phos-tag gels for phosphorylated isoforms
Immunoprecipitation followed by mass spectrometry:
Enrich CINV2 with a pan-CINV2 antibody
Perform tryptic digestion
Analyze peptide fragments by LC-MS/MS
Identify isoform-specific peptides
Recombinant protein controls: Express each isoform to validate antibody specificity and establish detection thresholds.
Computational validation: Use molecular docking predictions to assess antibody binding to different isoforms, similar to methods used to predict antibody binding to different viral variants .