At4g19890 (UniProt accession: P0C8Q3) is a protein found in Arabidopsis thaliana (Mouse-ear cress), a model organism widely used in plant molecular biology. This protein is encoded by the At4g19890 gene located on chromosome 4. While the specific functions of this protein are not comprehensively detailed in the provided resources, most Arabidopsis proteins designated with the "At" prefix followed by chromosomal location are involved in various cellular processes including signal transduction, metabolic pathways, or development regulation. Researchers typically use antibodies against these proteins to understand their localization, expression patterns, and interactions within plant cellular networks .
For optimal detection using At4g19890 Antibody (CSB-PA315422XA01DOA) in plant tissue samples, immunohistochemistry (IHC), Western blotting, ELISA, and immunofluorescence are commonly employed techniques. Western blotting typically requires sample optimization with 20-50 μg of total protein per lane. For immunohistochemistry applications, tissue fixation with 4% paraformaldehyde followed by antigen retrieval is recommended. The antibody generally performs best at dilutions between 1:500 to 1:2000 for Western blotting and 1:100 to 1:500 for IHC, though optimal concentrations should be determined experimentally for each application. PBS with 0.1% Tween-20 and 5% non-fat milk is recommended as a blocking solution to minimize background signals when working with plant tissue samples .
At4g19890 Antibody (CSB-PA315422XA01DOA) requires specific storage and handling protocols to maintain its functionality. The antibody is available in two size formats (2ml/0.1ml) and should be stored at -20°C for long-term stability. Avoid repeated freeze-thaw cycles by aliquoting the antibody upon first thaw. For working solutions, store at 4°C for up to one month. The antibody remains stable for at least 12 months when properly stored. Prior to use, centrifuge the vial briefly to collect solution at the bottom. For dilutions, use sterile buffers such as PBS with carrier proteins (0.1% BSA) to prevent adsorption to tube walls. Contamination with microorganisms should be strictly avoided as this can significantly reduce antibody activity .
When designing experiments with At4g19890 Antibody, multiple controls should be incorporated to ensure valid interpretation of results. Essential controls include:
Positive control: Arabidopsis thaliana tissue samples known to express the At4g19890 protein
Negative control: Samples from knockout lines where At4g19890 gene expression is disrupted
Secondary antibody control: Primary antibody omitted to assess non-specific binding of secondary antibody
Isotype control: Irrelevant antibody of the same isotype to evaluate non-specific binding
Blocking peptide control: Co-incubation with the immunizing peptide to confirm specificity
These controls help distinguish between specific signal and background noise, particularly important when working with plant tissues that may contain compounds interfering with antibody-antigen interactions .
Epitope mapping for At4g19890 Antibody validation requires a systematic approach to confirm specificity and identify potential cross-reactivity with related proteins. A recommended protocol involves:
Peptide array analysis: Generate overlapping peptides (15-20 amino acids) spanning the full At4g19890 protein sequence (UniProt P0C8Q3)
Alanine scanning: Create peptide variants with single amino acid substitutions to identify critical binding residues
Competition assays: Pre-incubate antibody with purified peptides prior to immunoassays
Mass spectrometry validation: Use immunoprecipitation followed by MS to confirm target capture
Bioinformatic analysis: Compare epitope sequences with other Arabidopsis proteins to predict potential cross-reactivity
This approach is particularly important for plant antibodies where homologous proteins from related gene families may share structural similarities. Researchers should document cross-reactivity with other proteins to properly interpret experimental results, especially when studying protein families with high sequence conservation .
For precise subcellular localization studies of the At4g19890 protein, optimized fractionation protocols should be employed:
| Fraction | Extraction Buffer | Centrifugation Parameters | Expected Markers |
|---|---|---|---|
| Cytosolic | 50mM HEPES (pH 7.5), 250mM sucrose, 5mM MgCl₂ | 10,000g, 15 min | GAPDH, aldolase |
| Nuclear | Previous pellet + 0.1% Triton X-100, DNase I | 16,000g, 20 min | Histone H3 |
| Membrane | Previous supernatant + 1M NaCl | 100,000g, 1 hour | PM H⁺-ATPase |
| Chloroplast | 330mM sorbitol, 50mM HEPES (pH 7.3) | Percoll gradient | LHCII, RuBisCO |
After fractionation, Western blot analysis using the At4g19890 Antibody (1:1000 dilution) should be performed on each fraction alongside fraction-specific marker antibodies. Immunofluorescence microscopy provides complementary data, using 3-4μm sections of fixed tissue and the antibody at 1:200 dilution. For definitive localization, co-localization studies with established organelle markers are essential to confirm subcellular distribution patterns .
When encountering weak or inconsistent signals in immunoprecipitation (IP) experiments with At4g19890 Antibody, a systematic troubleshooting approach is recommended:
Antibody binding optimization:
Increase antibody concentration (try 2-5 μg per 500 μg of total protein)
Extend incubation time to overnight at 4°C with gentle rotation
Test cross-linking with DSS or BS3 to stabilize antibody-bead complexes
Lysis buffer optimization:
Use plant-specific IP buffer (50mM Tris-HCl pH 7.5, 150mM NaCl, 1% NP-40, 0.5% sodium deoxycholate)
Add protease inhibitors freshly before each experiment
Include phosphatase inhibitors if phosphorylation status is important
Target protein considerations:
Verify expression levels with direct Western blot of input sample
Consider protein-specific extraction conditions (salt concentration, detergent type)
Test native versus denaturing conditions based on protein structure
Technical refinements:
Pre-clear lysates thoroughly (2 hours with Protein A/G beads)
Increase wash stringency gradually while monitoring signal
Elute with gentle conditions (glycine buffer pH 2.8) followed by immediate neutralization
Careful documentation of each modification is essential for developing an optimized protocol specific to the At4g19890 protein in Arabidopsis tissues .
For rigorous quantification of At4g19890 protein expression dynamics, multiple complementary approaches should be employed:
Quantitative Western blotting:
Use internal loading controls (actin or GAPDH) for normalization
Include recombinant protein standards for absolute quantification
Employ fluorescence-based detection systems (e.g., IRDye secondary antibodies)
Analyze with densitometry software ensuring signal is within linear range
ELISA-based quantification:
Develop sandwich ELISA using capture and detection antibodies
Generate standard curves with recombinant At4g19890 protein
Process all developmental stage samples simultaneously
Calculate coefficient of variation between technical replicates (<15%)
Image-based quantification:
Use confocal microscopy with consistent acquisition parameters
Employ automated image analysis for cell-specific quantification
Include fluorescence intensity standards in each experiment
Analyze 10-15 independent biological replicates per condition
For stress response studies, consistent stress application protocols and sampling times are critical. Protein extraction buffers may require optimization depending on tissue type (e.g., higher detergent concentrations for stress-modified tissues). Statistical analysis should include ANOVA with appropriate post-hoc tests when comparing multiple conditions .
Validation of At4g19890 Antibody specificity using genetic knockout lines requires a comprehensive approach:
Generate genetic controls:
T-DNA insertion lines targeting At4g19890 (check ABRC or NASC seed banks)
CRISPR/Cas9-mediated knockout lines with verified frameshift mutations
RNAi knockdown lines with confirmed reduction in transcript levels
Molecular verification:
Confirm gene disruption via PCR genotyping and sequencing
Verify transcript absence/reduction through RT-qPCR
Assess potential compensatory expression of related genes
Antibody validation protocol:
Perform Western blotting on wild-type vs. knockout tissue samples
Include recombinant At4g19890 protein as positive control
Test multiple tissue types to account for expression differences
Document absence of specific band in knockout samples
Quantitative assessment:
Compare signal intensities across multiple biological replicates
Calculate signal-to-noise ratio in wild-type vs. knockout samples
Document any non-specific bands that persist in knockout lines
Proper validation should demonstrate clear absence of the target band in knockout lines while preserving any non-specific signals, providing a definitive control for distinguishing specific from non-specific antibody interactions in experimental applications .
Multiple complementary techniques can be employed with At4g19890 Antibody to comprehensively investigate protein-protein interactions:
| Technique | Application | Advantages | Limitations |
|---|---|---|---|
| Co-immunoprecipitation | Pull-down of protein complexes | Detects native interactions | May miss transient interactions |
| Proximity Ligation Assay | In situ interaction detection | Single-molecule sensitivity | Requires two antibodies |
| BiFC (split YFP) | Visualization of interactions | Direct visualization | Potential for false positives |
| FRET/FLIM | Dynamic interaction analysis | Real-time measurements | Complex instrumentation |
| Cross-linking MS | Interaction interface mapping | Identifies binding domains | Technically challenging |
For co-immunoprecipitation, use 5μg of At4g19890 Antibody with 1mg total protein extract and mild detergent conditions (0.5% NP-40). When coupled with mass spectrometry, this approach can identify novel interaction partners. For proximity ligation assays, combine At4g19890 Antibody with antibodies against suspected interaction partners at 1:100 dilution. Confocal microscopy visualization should include z-stack acquisition to capture the three-dimensional distribution of interaction signals throughout plant tissues .
When analyzing quantitative data from At4g19890 Antibody experiments, robust statistical approaches should be implemented:
Experimental design considerations:
Perform power analysis to determine adequate sample size
Include at least 3-5 biological replicates per condition
Use randomization and blinding where possible
Include appropriate positive and negative controls
Data preprocessing:
Test for normality using Shapiro-Wilk or Kolmogorov-Smirnov tests
Check for homogeneity of variance with Levene's test
Apply appropriate transformations if assumptions are violated
Remove outliers only with statistical justification
Statistical tests for different experimental designs:
Two conditions: Student's t-test or Mann-Whitney U test
Multiple conditions: One-way ANOVA with Tukey or Bonferroni post-hoc
Time course studies: Repeated measures ANOVA or mixed-effects models
Correlation analyses: Pearson's or Spearman's correlation coefficients
Advanced analytics:
Principal component analysis for multivariate data
Hierarchical clustering for expression pattern identification
False discovery rate correction for multiple comparisons
Bayesian approaches for complex experimental designs
Analysis of IP-MS data generated using At4g19890 Antibody requires a sophisticated bioinformatic pipeline:
Raw data processing:
Peak detection and alignment across samples
MS/MS spectrum matching against Arabidopsis proteome database
False discovery rate control (typically <1% at protein level)
Label-free quantification of identified proteins
Specificity filtering:
Compare against IgG control or pre-immune serum pulldown
Apply fold-change threshold (typically >3-fold enrichment)
Calculate SAINT scores to estimate interaction probability
Filter against CRAPome database to remove common contaminants
Network construction and analysis:
Integrate with existing protein interaction databases
Apply Markov clustering to identify protein complexes
Calculate network parameters (centrality, betweenness)
Visualize using platforms like Cytoscape with GO term enrichment
Validation strategy:
Select top candidates for reciprocal co-IP validation
Confirm key interactions using orthogonal methods (Y2H, BiFC)
Correlate interaction patterns with co-expression data
Map interaction domains through truncation/mutation studies
For the At4g19890 protein specifically, researchers should pay particular attention to plant-specific modifications that may affect peptide identification. Include appropriate database parameters for post-translational modifications relevant to plant biology, such as phosphorylation, glycosylation, and ubiquitination .
Adapting At4g19890 Antibody for CLEM studies requires specialized protocols to preserve both fluorescence signal and ultrastructural details:
Sample preparation optimization:
Use high-pressure freezing followed by freeze substitution
Embed in acrylic resins (LR White or Lowicryl HM20)
Prepare ultrathin sections (70-100 nm) on finder grids
Perform mild antigen retrieval if necessary
Immunolabeling protocol:
Block with 1% BSA, 0.1% fish gelatin in PBS for 30 minutes
Apply At4g19890 Antibody at 1:50 dilution (higher than for routine IF)
Incubate overnight at 4°C in humid chamber
Use gold-conjugated secondary antibodies (6nm or 10nm particles)
Post-fix with 2% glutaraldehyde after immunolabeling
Fiducial marker application:
Apply fluorescent/gold dual-labeled fiducial markers
Image samples first by confocal microscopy
Transfer to electron microscope with minimal sample manipulation
Capture EM images at multiple magnifications
Data integration:
Use specialized CLEM software for image registration
Confirm protein localization at ultrastructural level
Quantify gold particle distribution relative to subcellular compartments
Generate 3D reconstructions from serial sections if necessary
This approach allows precise localization of At4g19890 protein within the context of plant cell ultrastructure, providing insights into its functional associations with specific organelles or membrane domains at nanometer resolution .
When adapting At4g19890 Antibody for ChIP applications to study DNA-protein interactions:
ChIP protocol adaptations:
Optimize crosslinking (1-3% formaldehyde for 10-15 minutes)
Sonicate chromatin to 200-500bp fragments
Use 5-10μg antibody per ChIP reaction
Include IgG control and input samples
Perform stringent washing to reduce background
Validation requirements:
Confirm antibody specificity for the crosslinked protein
Test antibody lot on Western blot of crosslinked samples
Perform ChIP-qPCR with known targets before sequencing
Include ChIP from knockout lines as negative control
Data analysis considerations:
Use appropriate peak calling algorithms (MACS2, SEACR)
Apply IDR (Irreproducible Discovery Rate) for replicate analysis
Perform motif enrichment analysis of binding regions
Integrate with transcriptome data to associate binding with function
Biological interpretation:
Map binding sites to genomic features (promoters, enhancers)
Identify co-occurring transcription factors
Analyze conservation of binding sites across related species
Correlate binding patterns with expression changes during development or stress
If At4g19890 protein has not previously been characterized as a DNA-binding protein, researchers should first confirm its nuclear localization and potential DNA-binding capacity through bioinformatic prediction and cellular fractionation studies .
Implementing super-resolution microscopy with At4g19890 Antibody requires specialized protocols:
Sample preparation for different super-resolution techniques:
STED: Use bright, photostable fluorophores (Atto647N, Abberior Star)
STORM/PALM: Employ photoswitchable dyes (Alexa647, mEos)
SIM: Standard fluorophores work but brightness is crucial
Optimize sample thickness (≤10μm for best results)
Antibody modifications:
Use directly labeled primary antibody when possible
For secondary antibody approach, use F(ab) fragments to reduce distance
Titrate antibody concentration to achieve optimal labeling density
For STORM, aim for approximately one fluorophore per 50-100nm²
Imaging parameters:
STED: 30-50% depletion laser power, pixel size ~20nm
STORM: 10,000-30,000 frames, 10-30ms exposure time
SIM: 15 raw images per reconstructed frame (5 phases, 3 angles)
Include fiducial markers for drift correction
Quantitative analysis:
Measure cluster sizes, distances, and densities
Apply ripley's K-function or DBSCAN for cluster analysis
Use molecular counting approaches through calibrated detection
Compare distributions statistically between conditions
This approach can reveal nanoscale organization of At4g19890 protein that is invisible to conventional microscopy, particularly important if the protein functions within multiprotein complexes or specific membrane domains. Calculate localization precision (typically 10-30nm) and resolution (50-150nm depending on technique) for proper interpretation of biological significance .
Developing multiplexed immunofluorescence protocols with At4g19890 Antibody requires careful planning:
Antibody compatibility assessment:
Confirm species origin of each primary antibody
Verify lack of cross-reactivity between secondaries
Test each antibody individually before multiplexing
Validate staining patterns match single-antibody controls
Sequential staining protocol:
Start with lowest-abundance target protein (often At4g19890)
Apply first primary antibody at 1:100 dilution (16h, 4°C)
Detect with species-specific secondary antibody
Apply blocking step between rounds (normal serum matching next primary)
Repeat for each additional target protein
Spectral considerations:
Use fluorophores with minimal spectral overlap
Apply linear unmixing if bleed-through occurs
Include single-fluorophore controls for accurate unmixing
Consider brightness matching for balanced visualization
Advanced multiplexing techniques:
Tyramide signal amplification for weak signals
Antibody stripping and reprobing (validate epitope preservation)
DNA-barcoded antibodies for highly multiplexed imaging
Cyclic immunofluorescence for 10+ targets on same section
For plant tissues specifically, address autofluorescence by including unstained controls and applying appropriate quenching methods (0.1% Sudan Black B or 10mM CuSO₄). Document co-localization quantitatively using Pearson's or Manders' coefficients rather than relying solely on visual assessment .
When confronted with discrepancies between At4g19890 protein levels (detected via antibody) and mRNA levels (measured by RT-qPCR or RNA-seq), systematic analysis is required:
Analytical validation:
Confirm antibody specificity through knockout controls
Verify primer specificity for transcript analysis
Assess dynamic range and linearity of both detection methods
Check for isoform-specific detection differences
Biological mechanisms to consider:
Post-transcriptional regulation (miRNA targeting, RNA stability)
Translational efficiency differences across conditions
Post-translational regulation affecting protein stability
Protein localization changes affecting extraction efficiency
Temporal considerations:
Implement time-course studies to detect temporal shifts
Consider time lag between transcription and translation
Measure both parameters in the same samples when possible
Calculate protein-to-mRNA ratios across conditions
Integrative analysis:
Correlate with proteomic data if available
Examine other proteins in same pathway for similar patterns
Consider systems-level feedback mechanisms
Develop mathematical models to explain the relationship
These discrepancies often reveal important regulatory mechanisms rather than methodological errors. Document these findings carefully as they may indicate novel regulatory pathways affecting At4g19890 expression in response to environmental conditions or developmental signals .
Adapting At4g19890 Antibody for cross-species applications requires careful consideration:
Cross-reactivity prediction:
Perform sequence alignment of At4g19890 orthologs
Focus on epitope region conservation
Calculate percent identity and similarity scores
Predict epitope accessibility in orthologous proteins
Protocol adaptations for different species:
Modify extraction buffers for species-specific compounds
Adjust detergent concentrations for different membrane compositions
Optimize fixation times based on tissue density differences
Increase antibody concentration for distant species (1.5-3x)
Validation strategy:
Western blot with recombinant proteins from target species
Peptide competition assays with species-specific peptides
Immunoprecipitation followed by mass spectrometry
Parallel testing of multiple antibody lots
Signal interpretation considerations:
Document band size differences due to species-specific modifications
Note subcellular localization differences that may occur
Consider expression level variations across species
Validate functional conservation of protein independently
For species with significant evolutionary distance from Arabidopsis, researchers may need to generate new antibodies against species-specific peptides if cross-reactivity is insufficient. Always include appropriate positive controls from Arabidopsis when comparing across species .
Distinguishing signal specificity in high-throughput applications requires robust controls and analysis:
Assay-specific control strategy:
Protein microarrays: Include gradient of purified antigen
Tissue microarrays: Incorporate knockout/knockdown samples
Flow cytometry: Use isotype and secondary-only controls
ELISA: Develop standard curves with recombinant protein
Statistical approaches:
Calculate signal-to-noise ratio for each sample
Determine detection threshold using ROC curve analysis
Apply multiple hypothesis testing correction
Implement machine learning for pattern recognition
Validation pipeline:
Select representative samples for orthogonal validation
Confirm key findings with independent antibody preparations
Correlate with orthogonal measurements where possible
Verify dose-response relationships for quantitative assays
Data visualization strategies:
Plot technical replicates to assess variability
Use background-subtracted values for comparisons
Implement data normalization across batches
Visualize statistical significance alongside effect size
For Arabidopsis-specific applications, consider using CRISPR-edited mutant lines expressing At4g19890 protein with epitope tags as definitive controls. This enables clear discrimination between specific and non-specific signals even in challenging high-throughput formats where traditional controls may be limited .
When preparing manuscripts incorporating At4g19890 Antibody data, researchers should adhere to comprehensive reporting standards:
Materials documentation:
Report complete antibody information (supplier, catalog number, lot)
Document validation methods performed in your laboratory
Specify exact dilutions and incubation conditions
Describe all controls included in experiments
Method transparency:
Provide detailed immunoblotting/immunostaining protocols
Include representative full blot/gel images in supplements
Describe image acquisition settings comprehensively
Detail all image processing steps and software used
Data presentation standards:
Show representative images alongside quantification
Include scale bars on all microscopy images
Provide molecular weight markers on all blot images
Present biological replicates (n≥3) with appropriate statistics
Interpretation guidelines:
Acknowledge antibody limitations where relevant
Distinguish between correlation and causation
Discuss alternative explanations for observed patterns
Connect findings to broader biological context
Adhere to journal-specific guidelines for antibody reporting, such as those from the Journal of Cell Biology or Plant Cell. Consider depositing detailed protocols in repositories like protocols.io to enhance reproducibility. Address reviewer concerns about antibody specificity with additional controls rather than dismissing them as beyond the scope of the study .
Several cutting-edge technologies show promise for extending At4g19890 Antibody applications:
Advanced imaging technologies:
Expansion microscopy for improved subcellular resolution
Lattice light-sheet microscopy for dynamic protein tracking
Cryo-electron tomography for protein complex visualization
4D imaging (3D + time) for developmental studies
Single-cell applications:
Antibody-based single-cell proteomics
CyTOF (mass cytometry) for multi-parameter analysis
Spatial transcriptomics combined with protein detection
Microfluidic approaches for single-cell signaling studies
Protein engineering approaches:
Nanobody development for improved penetration
Split-epitope complementation systems
Proximity-dependent labeling (BioID, APEX)
Optogenetic control of protein function
Computational integration:
Machine learning for automated image analysis
Integrative multi-omics data modeling
Virtual reality visualization of protein localization
Predictive modeling of protein dynamics
These technologies will enable increasingly sophisticated studies of At4g19890 protein biology, potentially revealing new functions and regulatory mechanisms. Researchers should consider establishing collaborations with technology development laboratories to implement these advanced approaches as they become available for plant systems .
The plant biology community can enhance antibody resources through collective efforts:
Validation initiatives:
Perform comprehensive cross-validation of commercial antibodies
Establish community databases documenting antibody performance
Develop standard operating procedures for validation
Share validation data in publications and repositories
Resource development:
Generate monoclonal antibodies against conserved epitopes
Develop recombinant antibody technologies for plants
Create epitope-tagged transgenic line collections
Establish plant-specific antibody production facilities
Quality control improvements:
Implement batch-to-batch validation procedures
Document antibody performance across multiple applications
Establish minimum reporting standards for publications
Create plant-specific antibody certification programs
Training and education:
Develop workshops on antibody validation techniques
Create online resources for troubleshooting
Establish mentor networks for methodology transfer
Incorporate antibody literacy in graduate education
By participating in these community efforts, researchers working with At4g19890 and other plant proteins can contribute to a more robust ecosystem of validated reagents. Consider partnering with antibody manufacturers to provide feedback on performance characteristics and suggest improvements for future production batches .
Researchers can leverage numerous computational tools to enhance At4g19890 Antibody research:
Sequence analysis resources:
UniProt (P0C8Q3) for protein annotation and conservation
TAIR for gene expression and interactome data
Phytozome for cross-species ortholog identification
BAR ePlant for integrated visualization of multiple datasets
Structural prediction tools:
AlphaFold for protein structure prediction
Epitope prediction algorithms (BepiPred, DiscoTope)
MolProbity for structure validation
PyMOL for visualization and epitope mapping
Experimental design support:
Primer3Plus for primer design for validation experiments
Benchling for CRISPR guide RNA design
CLC Main Workbench for restriction analysis
ImageJ with plant-specific plugins for image analysis
Data integration platforms:
Cytoscape for network visualization
R/Bioconductor for statistical analysis
Plant Reactome for pathway analysis
Bio-Analytic Resource for data mining