NDX Antibody is a polyclonal antibody raised in rabbits that specifically targets the NODULIN HOMEOBOX protein in Arabidopsis thaliana, commonly known as Mouse-ear cress, a model organism widely used in plant molecular biology research. The antibody is produced through immunization with recombinant Arabidopsis thaliana NDX protein and subsequently purified using antigen affinity methods to ensure high specificity . As a research tool, NDX Antibody enables scientists to investigate the complex roles of NDX in heterochromatin regulation, nuclear organization, and epigenetic control mechanisms.
The development of this antibody has facilitated significant advances in understanding plant chromatin dynamics and gene regulation. Unlike many other antibodies designed for mammalian systems, NDX Antibody is specifically optimized for plant research, addressing the unique challenges of studying plant-specific proteins and their functions. The antibody's high specificity for the NDX protein makes it an invaluable tool for researchers focused on plant epigenetics and chromatin biology.
The NDX Antibody is available in liquid form, supplied in a specialized buffer designed to maintain stability and activity. The antibody is non-conjugated, allowing researchers flexibility in selecting appropriate secondary detection methods based on their specific experimental requirements . Its polyclonal nature provides advantages in recognizing multiple epitopes on the target protein, potentially increasing detection sensitivity.
Table 1: Key Specifications of NDX Antibody
| Property | Specification |
|---|---|
| Product Code | CSB-PA447934XA01DOA |
| Clonality | Polyclonal |
| Host Species | Rabbit |
| Target Species | Arabidopsis thaliana |
| Immunogen | Recombinant Arabidopsis thaliana NDX protein |
| Isotype | IgG |
| Form | Liquid |
| Conjugate | Non-conjugated |
| Purification Method | Antigen Affinity Purified |
| UniProt Number | F4JI44 |
| Validated Applications | ELISA, Western Blot |
Understanding the target of NDX Antibody is crucial for interpreting experimental results and designing appropriate research protocols. The NDX protein has emerged as a key regulator of heterochromatin homeostasis in plants.
NODULIN HOMEOBOX (NDX) is a nuclear protein containing a homeodomain motif, which facilitates DNA binding. Microscopy studies using fluorescently tagged NDX reveal its distinct nuclear localization pattern. Confocal laser scanning microscopy shows strong NDX presence near the nuclear periphery, typically associated with perinuclear heterochromatin, with some cells also showing nucleolar localization . This spatial distribution provides important clues about NDX's functional roles in the nucleus.
Fluorescence correlation spectroscopy and fluorescence recovery after photobleaching analyses have confirmed NDX's association with chromocenters, which are densely packed heterochromatic regions visible in some plant cells . This localization pattern strongly suggests NDX's involvement in heterochromatin organization and maintenance.
Chromatin immunoprecipitation sequencing (ChIP-seq) has revealed that NDX binding sites are predominantly concentrated in centromeric and pericentromeric regions of Arabidopsis chromosomes. The density of NDX binding is significantly higher in these regions (84 peaks/Mb) compared to chromosomal arms (16 peaks/Mb) . This non-random distribution pattern reinforces NDX's association with gene-poor heterochromatic regions rather than transcriptionally active euchromatin.
Analysis of epigenomic landscapes shows that NDX binding sites preferentially associate with transcriptionally silent heterochromatin enriched in repressive histone marks (H3K9me2, H3K27me1), DNA methylation (CG/CHG/CHH), and transposable elements . Interestingly, NDX binding sites show strong anti-correlation with R-loop structures (RNA-DNA hybrids) that are typically enriched in transcriptionally active regions.
Recent research has significantly revised our understanding of NDX's primary functions, revealing its crucial role in heterochromatin regulation rather than as a simple euchromatic gene regulator as previously believed.
NDX functions primarily as a heterochromatin regulator in pericentromeric regions, controlling small interfering RNA (siRNA) production and non-CG methylation . Most NDX binding sites coincide with pericentromeric heterochromatic siRNA loci that mediate transposon silencing, suggesting a direct role in maintaining genome stability through transposon repression.
Studies of ndx mutant plants provide compelling evidence for NDX's role in heterochromatin maintenance. Inactivation of NDX leads to:
Differential siRNA accumulation
Altered DNA methylation patterns, particularly CHH/CHG hypomethylation at NDX binding sites
Significant chromatin structural changes, including decreased intrachromosomal interactions at pericentromeres
Increased interchromosomal contacts between KNOT-forming regions, similar to changes observed in DNA methylation mutants
An intriguing aspect of NDX function is its apparent antagonistic relationship with R-loop structures. Global mapping of RNA-DNA hybrids in ndx mutants revealed a moderate but statistically significant increase in R-loops compared to wild-type plants . This suggests that NDX may function to prevent excessive R-loop formation, potentially protecting genome integrity.
Both slot blot hybridization and DNA-RNA immunoprecipitation quantitative PCR (DRIP-qPCR) at selected genomic regions have confirmed elevated R-loop levels in ndx mutants . This negative regulatory relationship between NDX and R-loops provides new insights into how heterochromatin maintenance and R-loop dynamics may be coordinated in the plant genome.
NDX Antibody serves as a valuable tool in multiple research applications, particularly in the fields of plant molecular biology, epigenetics, and chromatin studies.
The manufacturer has validated NDX Antibody for several research applications, including:
Enzyme-Linked Immunosorbent Assay (ELISA): Useful for quantitative detection of NDX protein in various sample types.
Western Blotting (WB): Enables detection of NDX protein in plant tissue extracts, providing information about protein expression levels and molecular weight .
Beyond these validated applications, researchers have successfully employed similar antibodies in chromatin immunoprecipitation (ChIP) experiments to identify genome-wide binding patterns of NDX, as evidenced by studies using tagged NDX fusion proteins . This approach has been instrumental in mapping NDX binding sites across the Arabidopsis genome.
Given NDX's role in heterochromatin regulation, NDX Antibody is particularly valuable for research in:
Plant Epigenetics: Investigating DNA methylation patterns and their regulation in plant genomes.
Heterochromatin Dynamics: Studying the formation, maintenance, and functions of heterochromatic regions in plant nuclei.
Transposon Silencing Mechanisms: Exploring how plants control the activity of transposable elements through epigenetic mechanisms.
Nuclear Architecture Studies: Examining the spatial organization of chromatin within the nucleus and its functional consequences.
R-loop Biology: Investigating the formation and regulation of RNA-DNA hybrids and their impact on genome stability.
When working with NDX Antibody, several experimental considerations can help optimize results and ensure reliable data interpretation.
For Western blot applications, the recommended antibody concentration is determined through titration experiments to find the optimal dilution that provides specific signal with minimal background. Based on similar polyclonal antibodies targeting plant nuclear proteins, typical working dilutions range from 1:500 to 1:2000 for Western blotting applications, though specific optimization is recommended for each experimental context .
For immunofluorescence or immunocytochemistry applications, careful fixation and permeabilization protocols are essential to preserve nuclear architecture while allowing antibody access to nuclear proteins. Paraformaldehyde fixation (typically 4%) followed by detergent permeabilization is commonly employed for plant cells and tissues.
To ensure specificity and reliability in experiments using NDX Antibody, several controls should be considered:
Negative Controls: Including samples from ndx knockout or knockdown plants helps confirm antibody specificity.
Peptide Competition Assays: Pre-incubating the antibody with excess immunizing peptide should abolish specific signals if the antibody is truly specific.
Alternative Detection Methods: Confirming results with orthogonal techniques or alternative antibodies targeting different epitopes of the same protein increases confidence in experimental findings.
Loading Controls: For Western blot applications, appropriate loading controls should be used to normalize protein quantities across samples.
The development and application of NDX Antibody have enabled significant advances in understanding plant heterochromatin regulation, with several exciting research directions emerging in recent years.
Recent studies using NDX Antibody and related tools have revealed unexpected functions of NDX in genome organization. While initially described as a regulator of specific euchromatic genes, newer research has established NDX's primary role in heterochromatin maintenance . This paradigm shift highlights the importance of continuous reassessment of protein functions as new data emerge.
High-throughput chromosome conformation capture (Hi-C) analysis has shown that NDX influences higher-order chromatin structure, with ndx mutants exhibiting altered chromosomal interaction patterns . This finding connects NDX function to three-dimensional genome organization, suggesting broader roles in nuclear architecture beyond local heterochromatin maintenance.
Several promising research directions may benefit from the continued use and refinement of NDX Antibody:
Comparative studies across different plant species to determine the evolutionary conservation of NDX functions.
Investigation of potential NDX interactions with other chromatin-associated proteins through co-immunoprecipitation studies.
Exploration of NDX regulation in response to environmental stresses, potentially revealing dynamic aspects of heterochromatin control.
Development of improved antibody variants with enhanced specificity or conjugated to various reporter molecules for advanced imaging applications.
Examination of potential roles for NDX in plant development and cell differentiation, where chromatin reorganization plays crucial regulatory roles.
When reporting antibody use in scientific publications, researchers should include several critical pieces of information to ensure reproducibility. At minimum, you should report the antibody name, supplier, catalog number, and clone designation (for monoclonals) . Additionally, it's important to clearly specify:
The application the antibody was used for (e.g., Western blot, immunohistochemistry)
Working concentration or dilution used
Species reactivity and validation for your specific application
Batch/lot number, especially when batch variability is a concern
These details should be closely linked to the experimental techniques within your methods section rather than separated in a general materials list to avoid confusion. For studies involving multiple species, clearly indicate which antibodies were used with which species .
Antibody validation is critical for research reproducibility and should be addressed through multiple approaches:
If using an antibody in a previously validated application/species combination, cite the relevant publications
For novel applications or species, validation must be performed and reported, typically in supplementary information
The most rigorous validation methods include:
Remember that validation must be specific to your experimental conditions, as antibody specificity in one application (e.g., Western blot) does not guarantee specificity in another (e.g., immunofluorescence) . Journal guidelines increasingly require explicit validation information in submissions.
For optimal antibody preservation and activity:
Long-term storage: Aliquot antibodies and store at ≤ -20°C to prevent freeze-thaw cycles that can damage antibody structure
Before use: Centrifuge vials prior to removing the cap to ensure maximum recovery
Consider the storage buffer: Some antibodies are delivered in specialized buffers (e.g., 10 mM Tris, 50 mM Sodium Chloride, 0.065% Sodium Azide, pH 7.125) designed to maintain stability
Most commercial research antibodies have a shelf life of approximately 24 months from the date of receipt when stored properly . Always check manufacturer's specific recommendations as some antibodies may have unique storage requirements.
Designing antibodies with customized specificity profiles requires sophisticated computational and experimental approaches:
Leverage high-throughput sequencing combined with computational analysis to identify binding modes associated with specific ligands
Utilize phage display experiments to select antibody libraries against various combinations of ligands
Build computational models that can:
This approach allows the design of antibodies with either high specificity for a particular target ligand or cross-specificity for multiple target ligands . For example, researchers have successfully used biophysics-informed modeling combined with extensive selection experiments to create antibodies that can discriminate between very similar epitopes that cannot be experimentally dissociated from other epitopes present in the selection .
When developing multispecific antibodies for therapeutic applications, researchers should consider:
Clinical safety profiles: Recent studies show trispecific antibodies can have safety profiles similar to standard monoclonal antibodies
Pharmacokinetic properties: Monitor half-life to ensure it's comparable to standard monoclonal antibodies
Immunogenicity: Assess for minimal anti-drug antibody development, which can impact efficacy and safety
Target selection: Choose targets that benefit from simultaneous binding to multiple epitopes or antigens
Recent clinical data from multispecific antibodies, such as the trispecific broadly neutralizing antibody against HIV (SAR441236), provide support for the development of this antibody class . Early phase clinical studies have demonstrated feasibility for human use with similar half-life to standard monoclonal antibodies and minimal anti-drug antibody development .
When implementing antibody cocktails:
Evaluate individual antibody components for complementary activities
Assess potential synergistic effects that may enhance efficacy
Monitor for potential antagonistic interactions between components
Consider the viral/antigen escape mechanisms that each antibody targets
For example, Regeneron's REGN-COV2 antibody cocktail combined multiple antibodies to reduce viral loads and improve symptoms in COVID-19 patients . The cocktail showed greatest improvements in patients who had not mounted their own effective immune response prior to treatment (seronegative patients) . In seronegative patients, viral load reductions approached 99% compared to placebo, with significantly faster symptom resolution .
To address batch-to-batch variability:
Document batch/lot numbers in both laboratory notebooks and publications
When starting with a new batch:
Perform side-by-side validation with the previous batch
Test across concentration ranges to identify optimal working dilutions
Preserve small amounts of well-characterized batches as references
For critical experiments, purchase sufficient antibody from a single batch to complete the entire study
Batch variability is particularly problematic with polyclonal antibodies but can also affect monoclonal antibodies . When significant batch variability is observed, report this in publications to alert other researchers, and include the specific batch numbers used .
For challenging or poorly characterized targets:
Implement hierarchical validation strategies:
Begin with genetic approaches: Test antibody in knockout/knockdown systems
Employ multiple antibodies targeting different epitopes on the same protein
Use orthogonal methods to confirm findings (e.g., mass spectrometry)
Consider antigen characteristics:
For each application, validate specifically:
Western blot: Confirm molecular weight and band pattern
Immunofluorescence: Verify expected subcellular localization
Flow cytometry: Validate against known positive and negative cell populations
When analyzing antibody binding affinity data:
Model selection considerations:
Control for experimental artifacts:
For complex binding patterns:
Implement multivariate analysis to distinguish specific from non-specific binding
Use appropriate negative controls to establish baseline binding thresholds
Consider competitive binding assays to assess relative affinities
These approaches enable researchers to disentangle complex binding patterns, even when analyzing antibodies against very similar epitopes or when working with libraries containing numerous candidate antibodies .
When evaluating antibody efficacy in disease models:
Stratify subjects based on immunological status:
In COVID-19 studies, classifying patients as seronegative (no measurable antiviral antibodies) or seropositive (measurable antiviral antibodies) revealed that seronegative patients showed greater benefits from antibody treatment
This stratification helps identify subpopulations most likely to benefit from treatment
Establish clear, clinically relevant endpoints:
Dose-response assessment:
Monitoring safety parameters:
Implement these quality control measures when producing research-grade antibodies:
Production standardization:
Validation against overexpression systems:
Specificity verification:
Batch documentation:
These measures help ensure consistency and reliability of antibodies used in research applications.
Computational approaches are revolutionizing antibody research through:
Specificity prediction and design:
Modern computational models can identify binding modes associated with specific ligands
These models enable the design of antibodies with customized specificity profiles not present in experimental libraries
Researchers can now predict antibodies with either high specificity for particular targets or controlled cross-reactivity
Integration with experimental data:
Mitigating experimental limitations:
Computational approaches can address library size limitations in experimental selection
They can help identify and correct for experimental artifacts and biases in selection processes
Modeling at both amino acid and nucleotide levels confirms that selection is driven by protein-level interactions rather than codon biases
This combination of computational prediction with experimental validation represents a powerful toolset for designing antibodies with precisely controlled binding properties.
The development of multispecific antibodies faces several challenges: