Os09g0401200 Antibody

What is Os09g0401200 and what is its functional significance in rice?

Os09g0401200 encodes the TPR repeat-containing thioredoxin TDX (also known as OsTrx26 or Tetratricoredoxin). It belongs to the thioredoxin family of proteins that play critical roles in redox balance regulation through thiol-disulfide exchange reactions . Rice contains 10 members of h-type thioredoxins, with Os09g0401200 being one of them.

The protein contains the characteristic thioredoxin active site motif WCGPC, which is crucial for its redox functions. The presence of tetratricopeptide repeat (TPR) domains suggests that this protein is likely involved in protein-protein interactions and may function in stress response mechanisms in rice.

What are the key specifications of the Os09g0401200 Antibody?

The Os09g0401200 Antibody (product code: CSB-PA732309ZA01OFG) has the following specifications:

This antibody has been affinity-purified to enhance specificity against the target protein .

How should Os09g0401200 Antibody be stored and handled for optimal stability?

For optimal stability and activity retention:

• Upon receipt, store the antibody at -20°C or -80°C

• Avoid repeated freeze-thaw cycles as this can denature the antibody and reduce its efficacy

• If needed for regular use, prepare small working aliquots to minimize freeze-thaw cycles

• The antibody is provided in a storage buffer containing 50% glycerol, 0.01M PBS (pH 7.4), and 0.03% Proclin 300 as a preservative

• When handling, use sterile techniques and avoid contamination

• Prior to use, thaw the antibody at 4°C or on ice rather than at room temperature

• After thawing, gently mix the antibody by inverting the tube—do not vortex as this can denature the protein

How should researchers validate the Os09g0401200 Antibody before experimental use?

A comprehensive validation process should include:

• Positive and negative controls: Use rice tissues or cell lines known to express or lack Os09g0401200/TDX.

• Western blot validation: Run protein extracts from rice tissues alongside recombinant Os09g0401200 protein. A specific band should appear at the expected molecular weight (approximately 26 kDa for TDX).

• Cross-reactivity assessment: Test the antibody against protein extracts from related rice species or other plant models to determine specificity.

• Knockdown/knockout verification: If available, use RNAi lines or CRISPR-edited rice plants with reduced or eliminated Os09g0401200 expression. Similar to the approach used for OsTRXh1, where western blotting with anti-OsTRXh1 polyclonal antibody confirmed reduced protein expression in RNAi lines .

• Immunoprecipitation followed by mass spectrometry: Confirm that the immunoprecipitated protein is indeed Os09g0401200/TDX.

• Comparison with published literature: Check if band patterns and immunolocalization results match previously published data on TPR-containing thioredoxins.

How can Os09g0401200 Antibody be optimized for Western blot analysis of rice tissue samples?

For optimal Western blot results with Os09g0401200 Antibody:

• Sample preparation:

  • Extract total protein using a buffer containing reducing agents (e.g., DTT or β-mercaptoethanol) to preserve thioredoxin structure

  • Include protease inhibitors to prevent degradation

  • Consider subcellular fractionation to enrich for compartments where TDX is expressed

• Protein loading and separation:

  • Load 20-50 μg of total protein per lane

  • Use 12-15% SDS-PAGE gels for optimal separation of the expected 26 kDa TDX protein

  • Include molecular weight markers appropriate for small-medium sized proteins

• Transfer and blocking:

  • Use PVDF membrane (0.2 μm pore size) for better protein retention

  • Transfer at 100V for 1 hour or 30V overnight at 4°C

  • Block with 5% non-fat dry milk or BSA in TBS-T for 1 hour at room temperature

• Antibody incubation:

  • Dilute primary antibody (Os09g0401200 Antibody) 1:500 to 1:2000 in blocking buffer

  • Incubate overnight at 4°C with gentle rocking

  • Wash 4-5 times with TBS-T, 5 minutes each

  • Incubate with HRP-conjugated anti-rabbit secondary antibody (1:5000-1:10000)

  • Wash thoroughly before detection

• Detection and troubleshooting:

  • Use enhanced chemiluminescence (ECL) detection

  • If high background occurs, increase washing time/frequency and further dilute antibodies

  • If signal is weak, increase protein loading or reduce antibody dilution

  • Consider using signal enhancers if the protein is expressed at low levels

How can Os09g0401200 Antibody be used to investigate protein-protein interactions involving TDX?

To investigate protein-protein interactions involving TDX:

• Co-immunoprecipitation (Co-IP):

  • Use Os09g0401200 Antibody coupled to Protein A/G beads to pull down TDX and associated proteins

  • Extract proteins in non-denaturing conditions to preserve interactions

  • Identify interacting partners by mass spectrometry

  • Validate interactions by reverse Co-IP using antibodies against suspected interacting proteins

  Based on studies with related thioredoxins, TDX may interact with proteins involved in stress responses or redox signaling .

• Proximity-dependent labeling:

  • Fusion of TDX with BioID or APEX2

  • Use Os09g0401200 Antibody to confirm expression of the fusion protein

  • Identify proximal proteins by streptavidin pull-down and mass spectrometry

• Yeast two-hybrid validation:

  • Similar to the approach used for OsTrxh1/h4 where Y2H assays revealed interactions with OsPHO2

  • Use site-directed mutagenesis to identify key residues involved in interactions

  • Analyze the role of conserved WCGPC motif in interactions

• Bimolecular Fluorescence Complementation (BiFC):

  • As demonstrated with OsTrxh1/h4, BiFC in rice protoplasts can confirm in vivo interactions

  • Fuse TDX to the N-terminal fragment of YFP and potential interacting partners to C-terminal YFP

  • Analyze subcellular localization of interactions using appropriate markers

What methodological approaches should be used when studying Os09g0401200/TDX's role in oxidative stress responses?

To investigate TDX's role in oxidative stress responses:

• Expression analysis under stress conditions:

  • Expose rice plants to various stressors (salt, drought, heat, cold, pathogen)

  • Extract protein at different time points

  • Use Os09g0401200 Antibody for Western blot to quantify TDX protein levels

  • Compare with transcript levels using qRT-PCR

• Subcellular localization changes:

  • Perform immunofluorescence using Os09g0401200 Antibody on fixed rice tissues

  • Analyze potential relocalization of TDX during stress responses

  • Co-stain with organelle markers to determine precise localization

• Post-translational modifications (PTMs):

  • Immunoprecipitate TDX using Os09g0401200 Antibody

  • Analyze for PTMs (phosphorylation, oxidation, glutathionylation) by mass spectrometry

  • Determine how PTMs change during stress responses

• Functional analysis using transgenic plants:

  • Generate overexpression and RNAi/CRISPR lines for Os09g0401200

  • Verify protein levels using Os09g0401200 Antibody

  • Assess phenotypes under stress conditions

  • Measure redox-related parameters (ROS levels, antioxidant enzyme activities)

• Interaction network changes:

  • Perform Co-IP with Os09g0401200 Antibody under normal and stress conditions

  • Identify differential interactions that occur specifically during stress

  • Validate key interactions using alternative methods

How does Os09g0401200/TDX compare functionally with other thioredoxins in rice, and how can this antibody help elucidate these differences?

Comparative analysis of TDX with other rice thioredoxins:

• Cross-reactivity assessment:

  • Test Os09g0401200 Antibody against recombinant proteins of all 10 h-type thioredoxins in rice

  • Determine specificity using Western blot and ELISA

  • Establish optimal dilutions to minimize cross-reactivity

• Expression pattern comparison:

  • Use Os09g0401200 Antibody alongside antibodies against other thioredoxins

  • Compare protein levels across tissues, developmental stages, and stress conditions

  • Similar to studies with OsTRXh1, where antibodies were used to study protein expression patterns

• Functional redundancy analysis:

  • In transgenic lines with altered expression of multiple thioredoxins

  • Use Os09g0401200 Antibody to confirm specific knockdown/overexpression

  • Assess compensatory changes in other thioredoxins

• Domain-specific functions:

  • TPR repeat domains in TDX (unique among rice thioredoxins) likely mediate specific protein-protein interactions

  • Use Os09g0401200 Antibody to pull down interaction partners specific to TDX

  • Compare with interaction networks of other thioredoxins without TPR domains

• Redox activity comparison:

  • Measure the redox potential and enzymatic activity of TDX vs. other thioredoxins

  • Use Os09g0401200 Antibody to immunoprecipitate native TDX for activity assays

  • Correlate structural differences with functional differences

How can site-directed mutagenesis studies of Os09g0401200/TDX be validated using this antibody?

For validating site-directed mutagenesis studies:

• Epitope determination:

  • First determine if the Os09g0401200 Antibody recognizes an epitope that may be affected by your mutations

  • If targeting the WCGPC active site, verify antibody binding to mutants using dot blot before proceeding

• Mutant expression verification:

  • After generating mutations in the WCGPC motif or TPR domains

  • Use Os09g0401200 Antibody to confirm expression of mutated proteins

  • Similar to the approach used for OsTrxh1/h4 where mutations of the conserved cysteines (C40S, C43S in OsTrxh1; C56S, C59S in OsTrxh4) were studied

• Structure-function correlation:

  • Introduce mutations in key residues (particularly in the WCGPC motif)

  • Use Os09g0401200 Antibody in immunoprecipitation followed by activity assays

  • Correlate structural changes with functional outcomes

• Interaction studies with mutants:

  • Using Y2H, BiFC, or Co-IP approaches

  • Apply Os09g0401200 Antibody to verify that loss of interaction is not due to lack of expression

  • As demonstrated in the OsTrxh1/OsTrxh4 studies, where specific Cys residues were critical for interaction with OsPHO2

• Immunolocalization of mutant proteins:

  • Determine if mutations affect subcellular targeting

  • Use Os09g0401200 Antibody for immunofluorescence studies

  • Compare localization patterns between wild-type and mutant proteins

What are the considerations for using Os09g0401200 Antibody in immunohistochemistry and immunocytochemistry of plant tissues?

When using Os09g0401200 Antibody for plant tissue immunostaining:

• Tissue fixation and processing:

  • Fix tissues in 4% paraformaldehyde for 12-24 hours

  • Consider using a mixture of paraformaldehyde and glutaraldehyde (2%/0.1%) for better ultrastructural preservation

  • For paraffin embedding, use progressive dehydration series to prevent tissue shrinkage

  • For cryosectioning, infiltrate with sucrose (30%) before freezing

• Antigen retrieval optimization:

  • Plant tissues often require enhanced antigen retrieval

  • Test citrate buffer (pH 6.0) and Tris-EDTA (pH 9.0) for heat-induced epitope retrieval

  • Enzymatic retrieval with proteinase K may be necessary for heavily cross-linked samples

• Reducing background:

  • Plant tissues contain endogenous peroxidases and biotin

  • Block endogenous peroxidases with 3% H₂O₂ for 10 minutes

  • Block endogenous biotin with avidin/biotin blocking kit if using biotin-based detection

  • Include 0.1-0.3% Triton X-100 in blocking buffer to enhance penetration

• Antibody dilution optimization:

  • Test a range of dilutions (1:100 to 1:1000)

  • Incubate sections with primary antibody overnight at 4°C

  • Use fluorescent or enzymatic (HRP/AP) secondary detection systems

• Controls and validation:

  • Include a no-primary antibody control

  • Use tissues from Os09g0401200 knockdown/knockout plants as negative controls

  • Perform peptide competition assays to confirm specificity

How can Os09g0401200 Antibody be used in multiplexed immunoassays with other antibodies?

For multiplexed immunoassays:

• Antibody compatibility assessment:

  • Ensure secondary antibodies don't cross-react (use different host species or isotypes)

  • Verify that detection systems are compatible and distinguishable

  • Test antibodies individually before combining to establish baseline signals

• Sequential vs. simultaneous staining:

  • For immunofluorescence:

    • Test both simultaneous incubation of all primary antibodies

    • If cross-reactivity occurs, use sequential staining with blocking steps between each antibody

  • For chromogenic detection:

    • Always use sequential detection with different substrates

    • Begin with the weakest signal antibody

• Multiplexed Western blotting:

  • For fluorescent detection:

    • Use different fluorophores for each target protein

    • Ensure appropriate filter sets are available for imaging

  • For chemiluminescent detection:

    • Strip and reprobe, or use different colored substrates

    • Document complete stripping before reprobing

• Spatial analysis in plant tissues:

  • Combine Os09g0401200 Antibody with antibodies against:

    • Cellular compartment markers to determine precise localization

    • Other thioredoxins to compare distribution patterns

    • Potential interacting partners identified in protein-protein interaction studies

How should researchers approach epitope mapping of Os09g0401200 Antibody for better experimental design?

For epitope mapping of Os09g0401200 Antibody:

• Peptide array analysis:

  • Synthesize overlapping peptides (12-15 amino acids) spanning the entire TDX sequence

  • Incubate peptide array with Os09g0401200 Antibody

  • Identify reactive peptides to narrow down the epitope region

• Truncation analysis:

  • Generate a series of N- and C-terminally truncated TDX proteins

  • Express these in a heterologous system

  • Test reactivity by Western blot with Os09g0401200 Antibody

  • Progressively narrow down the region containing the epitope

• Site-directed mutagenesis:

  • Once a candidate epitope region is identified, create point mutations

  • Focus on charged and polar residues that often form antibody epitopes

  • Test each mutant for altered antibody binding

  • Similar to approaches used for characterizing interactions of thioredoxins

• Computational prediction:

  • Use epitope prediction algorithms to identify likely epitopes

  • Prioritize surface-exposed regions of the protein

  • Cross-reference predictions with experimental data

• Applications of epitope knowledge:

  • Design experiments to avoid mutations that might affect antibody binding

  • Develop blocking peptides for validation studies

  • Understand potential limitations of the antibody in certain experimental contexts

What approaches should be used when working with Os09g0401200 Antibody in plants exposed to environmental stressors?

When studying stress responses with Os09g0401200 Antibody:

• Sample collection and preservation:

  • Collect tissues at consistent times to control for diurnal variations

  • Flash-freeze samples immediately to preserve protein state and modifications

  • Process all samples simultaneously to minimize batch effects

• Protein extraction considerations:

  • Include higher concentrations of protease inhibitors as stress can activate proteases

  • Add phosphatase inhibitors to preserve potential stress-induced phosphorylation

  • Include reducing agents to preserve thioredoxin structure

  • Consider adding specific inhibitors based on the stressor (e.g., PMSF for heat stress)

• Quantification approaches:

  • Use internal loading controls appropriate for the stress being studied

  • Traditional housekeeping proteins may change under stress conditions

  • Consider total protein normalization methods (e.g., stain-free technology)

  • Perform time-course analyses to capture dynamic changes

• Detecting post-translational modifications:

  • Immunoprecipitate TDX with Os09g0401200 Antibody

  • Analyze by Western blot using modification-specific antibodies (phospho, ubiquitin, etc.)

  • Confirm by mass spectrometry analysis of the immunoprecipitated protein

• Stress-specific protocols:

  • For oxidative stress: include additional antioxidants in extraction buffers

  • For heat stress: perform protein extraction at 4°C with pre-chilled equipment

  • For salt/osmotic stress: adjust buffer ionic strength to maintain protein solubility

How can Os09g0401200 Antibody be used to validate CRISPR/Cas9 or RNAi-mediated gene modifications?

For validating genetic modifications:

• Verification of protein depletion in knockdown/knockout lines:

  • Extract total protein from wild-type and modified plant lines

  • Perform Western blot analysis using Os09g0401200 Antibody

  • Quantify signal reduction relative to loading controls

  • Similar to the approach used for OsTRXh1 RNAi lines, where protein expression reduction was confirmed by Western blot using anti-OsTRXh1 polyclonal antibody

• Mosaic analysis in chimeric plants:

  • Use immunohistochemistry with Os09g0401200 Antibody

  • Identify sectors with successful editing vs. non-edited tissues

  • Particularly useful for evaluating CRISPR efficiency in primary transformants

• Partial modifications analysis:

  • For in-frame mutations or domain deletions

  • Detect size shifts in the protein using Western blot

  • Assess stability of modified proteins

• Off-target assessment:

  • Check expression of related thioredoxins using specific antibodies

  • Ensure that RNAi or CRISPR specifically targets Os09g0401200

  • Similar to the verification done for OsTRXh1 RNAi lines, where expression of other Trx family members (OsTRXh3, OsTRXh4) was monitored to confirm specificity

• Complementation studies validation:

  • Verify expression of reintroduced wild-type or modified Os09g0401200

  • Confirm proper localization and expression levels

  • Correlate with phenotypic rescue

What are effective protocols for using Os09g0401200 Antibody in chromatin immunoprecipitation (ChIP) experiments?

If TDX functions as a nuclear protein or associates with chromatin-bound proteins:

• Cross-linking optimization:

  • Test different formaldehyde concentrations (1-3%) and cross-linking times (10-30 minutes)

  • For plant tissues, vacuum infiltration of fixative improves penetration

  • Include a glycine quenching step to stop cross-linking

• Chromatin extraction and fragmentation:

  • Grind tissue in liquid nitrogen before adding nuclear isolation buffer

  • Filter through miracloth to remove debris

  • Optimize sonication conditions to achieve 200-500 bp fragments

  • Verify fragmentation by agarose gel electrophoresis

• Immunoprecipitation protocol:

  • Pre-clear chromatin with protein A/G beads

  • Incubate cleared chromatin with Os09g0401200 Antibody overnight at 4°C

  • Include appropriate controls:

    • Input chromatin (pre-IP sample)

    • No-antibody control

    • IgG control from the same species

    • Ideally, chromatin from knockout/knockdown plants

• Washing and elution:

  • Use increasingly stringent wash buffers to reduce background

  • Elute in multiple steps to improve recovery

  • Reverse cross-links by heating at 65°C overnight

• DNA purification and analysis:

  • Treat with RNase A and Proteinase K

  • Purify DNA using column or phenol-chloroform extraction

  • Analyze by qPCR targeting candidate regions or by sequencing (ChIP-seq)

• Data interpretation considerations:

  • As TDX is not known to bind DNA directly, focus on co-ChIP with known DNA-binding proteins

  • Look for enrichment at promoters of redox-responsive genes

  • Consider the possibility of indirect DNA association through protein complexes

How can sequence variations in Os09g0401200 across rice varieties impact antibody reactivity?

Addressing sequence variation impacts:

• Sequence alignment analysis:

  • Compare Os09g0401200 sequences across rice varieties and wild relatives

  • Identify polymorphic regions that might affect epitope recognition

  • Pay particular attention to variations in conserved domains vs. variable regions

• Cross-reactivity testing:

  • Test Os09g0401200 Antibody against protein extracts from different rice varieties

  • Include both japonica and indica subspecies

  • Quantify signal differences under identical conditions

• Recombinant protein controls:

  • Express Os09g0401200 variants from different rice cultivars

  • Test antibody reactivity against purified proteins

  • Use as standards for quantification in experimental samples

• Epitope-specific considerations:

  • If epitope mapping has been performed, check for variants specifically in the epitope region

  • Design experiments to account for potential false negatives in varieties with epitope variations

• Validation strategies:

  • Use multiple detection methods when working with diverse rice germplasm

  • Consider developing variety-specific calibration curves

  • Include positive controls from Oryza sativa subsp. japonica, the immunogen species

How should researchers interpret unexpected band patterns when using Os09g0401200 Antibody in Western blots?

When encountering unexpected bands:

• Expected vs. observed patterns:

  • TDX should appear at approximately 26 kDa

  • Higher molecular weight bands may indicate:

    • Post-translational modifications (phosphorylation, SUMOylation)

    • Dimerization or complex formation resistant to denaturation

    • Cross-reactivity with related proteins

  • Lower molecular weight bands may indicate:

    • Proteolytic degradation

    • Alternative splicing variants

    • Cross-reactivity with degradation products

• Methodical troubleshooting approach:

  • Vary sample preparation conditions (stronger reducing agents, different detergents)

  • Test different extraction buffers with various protease inhibitor combinations

  • Perform peptide competition assays to identify specific vs. non-specific bands

  • Compare patterns from different tissues and developmental stages

• Post-translational modification analysis:

  • Use phosphatase treatment to identify phosphorylated forms

  • Test deglycosylation enzymes if glycosylation is suspected

  • Perform immunoprecipitation followed by mass spectrometry

• Cross-reactivity assessment:

  • Test the antibody against recombinant proteins of related thioredoxins

  • Compare band patterns from wild-type and Os09g0401200 knockdown/knockout plants

  • Consider the possibility of splice variants or processed forms

What approach should be taken when Os09g0401200 Antibody shows inconsistent results between different experimental techniques?

When results differ between techniques:

• Technique-specific considerations:

  • Western blot vs. ELISA discrepancies:

    • Western blot detects denatured epitopes; ELISA often uses native proteins

    • Epitope accessibility differs between techniques

    • Quantification methods vary in sensitivity and dynamic range

  • Immunofluorescence vs. biochemical assays:

    • Fixation can alter epitope structure or accessibility

    • Low expression may be detectable by Western blot but not by immunofluorescence

    • Subcellular compartmentalization may affect extraction efficiency

• Systematic validation approach:

  • Compare results using multiple antibody dilutions for each technique

  • Include recombinant Os09g0401200 protein as positive control

  • Test different buffer conditions and sample preparation methods

  • Use knockout/knockdown plants as negative controls

• Correlation analysis:

  • Compare protein detection with mRNA levels by qRT-PCR

  • Assess correlation between techniques across multiple samples

  • Look for consistent patterns even if absolute values differ

• Documentation and standardization:

  • Record batch numbers and storage conditions of antibodies

  • Standardize protocols across experiments

  • Include detailed methodological descriptions in publications

How can researchers distinguish between direct and indirect effects when studying Os09g0401200/TDX function using this antibody?

To distinguish direct vs. indirect effects:

• Temporal analysis approaches:

  • Perform detailed time-course experiments

  • Direct effects typically occur more rapidly than indirect effects

  • Use inducible expression systems to control timing of TDX expression

• Domain-specific mutant analysis:

  • Generate catalytically inactive TDX (mutations in WCGPC motif)

  • Create TPR domain mutants that maintain redox activity but alter interactions

  • Use Os09g0401200 Antibody to confirm equivalent expression levels of mutants

  • Similar to approaches used for studying OsTrxh1/h4 where specific cysteine residues were mutated

• Substrate trapping approaches:

  • Create "substrate-trapping" mutants (e.g., WCGPS) that form stable interactions with targets

  • Immunoprecipitate using Os09g0401200 Antibody

  • Identify trapped substrates by mass spectrometry

• In vitro reconstitution:

  • Purify recombinant TDX using affinity methods

  • Test direct redox activity on candidate proteins

  • Compare with in vivo results using the antibody

• Integration with other data types:

  • Correlate protein-level changes (detected with antibody) with:

    • Transcriptomic changes

    • Metabolomic alterations

    • Post-translational modification profiles

  • Use network analysis to distinguish direct targets from downstream effects