NUMA1 Antibody

What is NUMA1 and what cellular functions does it perform?

NUMA1 is a high molecular weight (238 kDa) protein encoded by the NUMA1 gene in humans, with five identified isoforms . It has a dual localization pattern: residing exclusively in the nuclear matrix during interphase and associating with spindle poles during mitosis .

The protein structure consists of:

• Globular head and tail domains separated by a 1500 amino acid discontinuous coiled-coil

• A C-terminus containing a nuclear localization signal (NLS)

• A 100 amino acid stretch that directly binds and bundles microtubules

• Several S/TPXX motifs in both globular domains, sequences typically found in gene regulatory proteins

NUMA1's major functions include:

• Forming complexes with dynein and dynactin to stabilize microtubule-centrosome interactions at spindle poles

• Regulating spindle positioning and asymmetric cell division alongside Gα and LGN

• Potentially functioning as a nuclear scaffold supporting genome organization

• Tethering the minus ends of microtubules at spindle poles, critical for spindle pole establishment and maintenance

How do different NUMA1 antibodies perform across various experimental applications?

NUMA1 antibodies show varied performance across applications, as demonstrated by validation data from multiple suppliers:

For optimal results, researchers should:

• Perform antibody titration in each testing system

• Consider tissue-specific optimization of antigen retrieval methods

• Validate results with appropriate positive and negative controls

What are the best practices for storage and handling of NUMA1 antibodies?

Most NUMA1 antibodies require careful handling to maintain activity. Standard recommendations include:

• Store at -20°C for long-term stability (typically one year from receipt)

• After reconstitution of lyophilized antibodies, store at 4°C for up to one month

• Consider aliquoting reconstituted antibodies and storing frozen at -20°C for up to six months to avoid repeated freeze-thaw cycles

• For liquid formulations, many suppliers provide them in PBS with 0.02% sodium azide and 50% glycerol (pH 7.3)

• Some products are shipped in wet ice or dry ice, which should be considered when planning orders

When working with NUMA1 antibodies for critical experiments, researchers should:

• Avoid repeated freeze-thaw cycles

• Follow supplier-specific recommendations, as buffer compositions may affect stability

• Check expiration dates and validation data before use in important experiments

What is the relationship between NUMA1 and NMP22 antibody targets?

NMP22 (Nuclear Matrix Protein 22) is actually a reported synonym of the NUMA1 gene product . This creates potential confusion in the literature and commercial antibody designations:

• NMP22 antibodies and NUMA1 antibodies target the same protein, though they may recognize different epitopes

• The human version of NMP22/NUMA1 has a canonical amino acid length of 2115 residues and a protein mass of 238.3 kilodaltons

• This protein is widely expressed in many tissue types and functions in cell division and keratinocyte differentiation

• NMP22 has been documented as a cancer marker, particularly in bladder cancer diagnostics

Researchers should be aware that when searching for antibodies against this target, both designations may be used by different suppliers, and cross-referencing may be necessary to find the most appropriate reagent for specific applications .

How can NUMA1 antibodies be optimized for studying cancer biology?

NUMA1 has emerging significance in cancer research, particularly in esophageal squamous cell carcinoma (ESCC). Optimizing antibody-based approaches requires consideration of several factors:

NUMA1 expression patterns in cancer:

Methodological approaches for cancer research:

• For tissue microarray analysis, immunohistochemical staining using optimized NUMA1 antibodies has successfully differentiated between cancer and adjacent tissues

• For xenograft models, lentivirus-mediated NUMA1 knockdown has demonstrated significant impacts on tumor growth, providing a model system for antibody validation

• For mechanism studies, combine NUMA1 antibodies with antibodies against apoptotic markers (cleaved-PARP, cleaved caspase-3, Bim, Bcl-2) and cell cycle regulators (cyclin D1, cyclin D3)

When using NUMA1 antibodies in cancer tissue analysis:

• Optimize antigen retrieval using EDTA buffer (pH 8.0) for better epitope exposure

• Consider using a detection system like HRP Conjugated IgG Super Vision Assay with DAB as chromogen

• Include appropriate positive controls (known NUMA1-expressing cancer tissues) and negative controls

What techniques are effective for studying NUMA1's role in apoptosis using antibody-based approaches?

Evidence suggests NUMA1 modulates apoptosis in cancer cells, particularly in ESCC. Effective techniques for investigating this role include:

For cellular apoptosis assessment:

• TUNEL assay combined with NUMA1 immunostaining to correlate NUMA1 expression with apoptotic events

• Flow cytometry with annexin-V staining following NUMA1 knockdown/overexpression to quantify apoptotic cell populations

For mechanistic investigations:

• Co-immunoprecipitation using NUMA1 antibodies to identify interaction partners in apoptotic pathways

• Western blot analysis to correlate NUMA1 expression with key apoptotic markers:

  • Cleaved-PARP

  • Cleaved caspase-3

  • Short isoform of Bim (pro-apoptotic)

  • Bcl-2 (anti-apoptotic)

For pathway analysis:

• Combined immunofluorescence for NUMA1 and components of the ASK1-JNK signaling pathway

• Phospho-specific antibodies (p-SAPK/JNK (Thr183/Tyr185) and p-c-Jun (Ser73)) in conjunction with NUMA1 antibodies to study signaling cascade activation

Research has shown that silencing NUMA1 expression significantly enhanced ESCC cell apoptosis, upregulated pro-apoptotic markers (cleaved-PARP, cleaved caspase-3, Bim) and downregulated anti-apoptotic Bcl-2, suggesting multiple methodological approaches to dissect this relationship .

What methodological considerations should be taken when using NUMA1 antibodies in multiplex immunofluorescence experiments?

Multiplex immunofluorescence allows simultaneous visualization of NUMA1 with other proteins, providing insights into spatial relationships and co-localization. Key considerations include:

Antibody compatibility and panel design:

• Select NUMA1 antibodies raised in different host species than other target antibodies

• Consider using directly conjugated antibodies to avoid cross-reactivity

• Validate each antibody individually before multiplexing

Optimized protocol elements:

• For multi-color IF analysis with NUMA1, successful staining has been achieved using:

  • Enzyme antigen retrieval (particularly for U2OS cells)

  • Cell fixation with 4% paraformaldehyde

  • Blocking with 10% goat serum

  • Incubation with 5 μg/mL NUMA1 antibody overnight at 4°C

  • Secondary detection with species-specific fluorophore-conjugated antibodies

Successful multiplex combinations:

• NUMA1 + β-Tubulin: Demonstrated successful co-staining in U2OS cells using rabbit anti-NUMA1 and mouse anti-β-Tubulin primary antibodies, followed by Cy3-conjugated anti-rabbit and DyLight488-conjugated anti-mouse secondary antibodies

• For spindle pole visualization: Combine NUMA1 with centrosomal markers like γ-tubulin

• For nuclear organization studies: Combine with lamin or other nuclear matrix proteins

Controls and troubleshooting:

• Include single-stained controls for spectral unmixing

• Consider sequential rather than simultaneous incubation if cross-reactivity occurs

• Use appropriate nuclear counterstain (DAPI) at optimized concentration

How can researchers analyze NUMA1's associations with the spindle apparatus using antibody-based techniques?

NUMA1's critical role in spindle formation and maintenance requires specialized approaches for analysis:

Immunofluorescence optimization for spindle visualization:

• Fix cells at specific mitotic stages (metaphase, anaphase) using either paraformaldehyde or methanol fixation

• Consider cold-stable microtubule assays (4°C treatment before fixation) to visualize kinetochore fibers

• Co-stain with α-tubulin to visualize spindle microtubules and NUMA1 localization

Advanced microscopy approaches:

• Super-resolution microscopy (SIM, STED, or STORM) for detailed spindle pole architecture

• Live-cell imaging with fluorescently tagged NUMA1 to track dynamics during mitosis

• Correlative light and electron microscopy (CLEM) for ultrastructural context

Biochemical approaches:

• Chromatin immunoprecipitation (ChIP) to analyze NUMA1's association with specific DNA regions

• Proximity ligation assay (PLA) to detect and quantify NUMA1's close associations with other proteins

• Microtubule co-sedimentation assays using NUMA1 antibodies for detection

Data analysis considerations:

• Quantify NUMA1 fluorescence intensity at spindle poles relative to cytoplasmic background

• Measure spindle pole focusing and spindle length in NUMA1-depleted vs. control cells

• Analyze chromosome congression and segregation defects in relation to NUMA1 dysfunction

What approaches are most effective for studying NUMA1's interactions with phosphoinositides using antibodies?

Recent research has revealed NUMA1's interaction with phosphoinositides, particularly at the cell cortex during mitosis. Effective approaches include:

Co-localization studies:

• Use specialized probes for phosphoinositides (e.g., PH domains fused to fluorescent proteins)

• Perform dual immunostaining for NUMA1 and lipid-binding proteins

• Apply super-resolution microscopy to resolve membrane-associated NUMA1

Biochemical validation:

• Lipid overlay assays using recombinant NUMA1 followed by detection with NUMA1 antibodies

• Liposome co-sedimentation assays

• Surface plasmon resonance (SPR) to quantify binding kinetics

Protein domain mapping:

• Generate truncated NUMA1 constructs to identify phosphoinositide-binding domains

• Perform site-directed mutagenesis of candidate binding sites

• Use domain-specific antibodies to validate binding regions

Functional assays:

• Analyze cortical NUMA1 localization after manipulation of phosphoinositide levels

• Assess effects on spindle positioning and orientation

• Quantify dynein-dynactin recruitment in relation to NUMA1-phosphoinositide interaction

Research has shown that NUMA1 can directly associate with phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and other polyanionic phosphoinositides (PIP, LPA, PIP3), mediating recruitment of dynein-dynactin to the cell membrane during anaphase and thus regulating spindle elongation and chromosome segregation .

How can researchers optimize NUMA1 antibody performance for Western blot applications?

Western blotting for NUMA1 presents challenges due to its high molecular weight (238 kDa). Optimization strategies include:

Sample preparation:

• Use phosphatase inhibitors to preserve potential phosphorylation sites

• Consider mechanical rather than sonication-based lysis to preserve protein integrity

• Maintain low temperatures throughout sample processing

Gel electrophoresis considerations:

• Use lower percentage gels (6-8%) for better resolution of high molecular weight proteins

• Extend running time to properly separate NUMA1 from other large proteins

• Consider gradient gels for simultaneous analysis of NUMA1 and smaller proteins

Transfer optimization:

• Apply extended transfer times for high molecular weight proteins

• Consider semi-dry transfer with specialized buffers for large proteins

• Reduce methanol concentration in transfer buffer to improve elution of large proteins

Detection recommendations:

• Dilution range of 1:500-1:2000 for most NUMA1 antibodies

• Extended primary antibody incubation (overnight at 4°C)

• Validated positive controls include HeLa cell lysates

Based on validation data, researchers have successfully detected NUMA1 in human, mouse, and rat samples using these optimized conditions, with the expected band appearing at approximately 238 kDa .

What strategies can address common challenges in NUMA1 immunohistochemistry?

NUMA1 immunohistochemistry requires careful optimization, particularly for cancer tissues. Common challenges and solutions include:

Antigen retrieval methods:

• EDTA buffer (pH 8.0) has demonstrated superior results compared to citrate buffer

• Heat-mediated antigen retrieval is essential for proper epitope exposure

• For enzyme-based retrieval, carefully optimize incubation time (typically 15 minutes)

Background reduction:

• Block with 10% goat serum (or serum matching secondary antibody host)

• Consider additional blocking with BSA or commercial blocking reagents

• Use antibody dilutions in the 1:50-1:500 range, optimized for each tissue type

Signal amplification for low expression:

• Consider polymer-based detection systems

• Use HRP-conjugated secondary antibodies with DAB as chromogen

• Tyramide signal amplification for challenging samples

Tissue-specific considerations:

• Successfully validated in multiple cancer types: breast cancer, esophageal squamous carcinoma, lung cancer, and prostate adenocarcinoma

• Ensure proper controls from the same tissue type

• Consider counterstaining optimization based on tissue morphology

NUMA1 antibodies have been successfully used to demonstrate differential expression between cancer tissues and adjacent normal tissues, with several validated antibodies showing strong nuclear staining in interphase cells and spindle pole localization in mitotic cells .

How can conflicting NUMA1 expression data between different assay methods be reconciled?

Researchers sometimes encounter discrepancies in NUMA1 expression data when using different detection methods. Strategies to address this include:

Common sources of discrepancy:

• Antibody epitope accessibility varies between applications

• Post-translational modifications may affect antibody recognition

• Protein conformation differences in fixed versus denatured samples

• Cross-reactivity with NUMA1 isoforms

Methodological reconciliation approaches:

• Validate findings with multiple antibodies recognizing different epitopes

• Correlate protein data with mRNA expression analysis (RT-PCR or RNA-seq)

• Use orthogonal techniques (e.g., mass spectrometry) for protein identification

• Consider isoform-specific detection methods

Specific recommendations for NUMA1:

• When possible, use antibodies validated across multiple applications

• Consider that nuclear matrix extraction methods may affect NUMA1 detection

• For cancer studies, correlate IHC findings with Western blot and mRNA data

• Document mitotic index of samples, as NUMA1 localization changes dramatically during mitosis

Research has demonstrated that integrating multiple detection methods provides the most reliable assessment of NUMA1 expression, particularly in complex samples like heterogeneous tumors where cellular composition can significantly impact results .

How can NUMA1 antibodies contribute to cancer biomarker development?

NUMA1's emerging role in cancer biology suggests potential as a biomarker. Antibody-based approaches to exploring this include:

Evidence for biomarker potential:

Methodological approaches for biomarker development:

• Tissue microarray analysis with standardized NUMA1 antibody protocols

• Quantitative image analysis of NUMA1 immunostaining

• Correlation of NUMA1 expression with established prognostic factors

• Multi-marker panels combining NUMA1 with other cancer biomarkers

Clinical validation considerations:

• Standardize antibody clones and detection protocols for clinical application

• Establish scoring systems for NUMA1 expression levels

• Validate across multiple patient cohorts with diverse demographics

• Correlate with treatment response and survival outcomes

Research has shown that NUMA1 expression was not significantly correlated with clinical stage, lymph node metastasis, age, or gender in ESCC, suggesting it may provide independent prognostic information beyond established clinical parameters .

What are promising research directions for NUMA1 antibodies in studying cell division mechanisms?

NUMA1's central role in mitosis presents several promising research avenues:

Spindle pole organization:

• High-resolution mapping of NUMA1 interactions at spindle poles using proximity labeling approaches

• Analysis of NUMA1's role in centrosome-independent spindle assembly

• Investigation of NUMA1's interactions with other spindle pole proteins using co-immunoprecipitation and super-resolution microscopy

Asymmetric cell division:

• NUMA1's role in establishing cell polarity during asymmetric divisions

• Contribution to stem cell fate determination

• Interaction with cell cortex components in oriented divisions

Chromosome segregation:

• NUMA1's influence on kinetochore-microtubule attachments

• Role in correcting merotelic attachments

• Contribution to the spindle assembly checkpoint

Therapeutic targeting:

• Antibody-based approaches to disrupt NUMA1 function in cancer cells

• Development of small molecule inhibitors targeting NUMA1-dependent processes

• Exploration of synthetic lethality approaches in NUMA1-overexpressing cancers

Research using NUMA1 antibodies has already established its requirement for maintenance and establishment of mammalian spindle poles, and future work will likely expand our understanding of its regulatory mechanisms and potential as a therapeutic target .

How might emerging technologies enhance NUMA1 antibody applications in research?

Several emerging technologies hold promise for advancing NUMA1 research:

Spatial transcriptomics and proteomics:

• Combining NUMA1 immunostaining with spatial transcriptomics for contextual expression analysis

• Multiplex protein mapping to understand NUMA1's relationships with interacting partners

• Single-cell proteomics to reveal cell-specific NUMA1 expression patterns and functions

Advanced imaging approaches:

• Lattice light-sheet microscopy for live-cell dynamics of NUMA1 during mitosis

• Expansion microscopy for nanoscale organization of NUMA1 at spindle poles

• Cryo-electron tomography for structural insights into NUMA1-containing complexes

Genome and protein engineering:

• CRISPR-based endogenous tagging of NUMA1 for live-cell studies

• Split-protein complementation assays for studying NUMA1 interactions

• Optogenetic approaches to spatiotemporally control NUMA1 function

Computational methods:

• Machine learning for automated analysis of NUMA1 distribution patterns

• Molecular dynamics simulations of NUMA1-microtubule interactions

• Network analysis to position NUMA1 within broader cellular pathways

These technologies, combined with high-quality NUMA1 antibodies, will enable researchers to address fundamental questions about nuclear architecture, spindle assembly, and chromosome segregation with unprecedented resolution and precision.