N4BP2L2 Antibody

What is N4BP2L2 and what are its key biological functions?

N4BP2L2, also known as PFAAP5 (phosphonoformate immuno-associated protein 5), is a 583 amino acid nuclear protein potentially involved in transcriptional regulation. This protein is primarily expressed in bone marrow and undergoes significant down-regulation following exposure to arsenic compounds, an event preceding neutropenia development . N4BP2L2 interacts with both Gfi-1 and Neutrophil Elastase, two proteins implicated in neutropenia disorders . The protein is phosphorylated on Ser 199 in response to DNA damage, likely by ATM or ATR kinases, suggesting a role in cellular stress response pathways .

What types of N4BP2L2 antibodies are available for research applications?

Researchers have access to both polyclonal and monoclonal antibodies targeting N4BP2L2:

These antibodies have been developed against specific recombinant protein sequences and validated for different applications . Selection should be based on your specific experimental requirements and target species.

What is the optimal protocol for using N4BP2L2 antibodies in immunocytochemistry?

For immunocytochemistry/immunofluorescence applications using polyclonal N4BP2L2 antibodies, the following methodology is recommended:

• Fix cells using a standard paraformaldehyde protocol

• Permeabilize with 0.1% Triton X-100 in PBS

• Block with 1-5% BSA or normal serum from the same species as the secondary antibody

• Incubate with primary N4BP2L2 antibody at 1-4 μg/mL concentration in blocking buffer overnight at 4°C

• Wash 3x with PBS

• Incubate with fluorophore-conjugated secondary antibody

• Counterstain nuclei and mount for visualization

The antibody specifically detects N4BP2L2 in human samples and has been validated for this application through specificity testing against 383 non-specific proteins .

How should N4BP2L2 antibodies be stored and handled to maintain optimal activity?

Proper storage and handling of N4BP2L2 antibodies is critical for maintaining their activity. Polyclonal antibodies from Novus Biologicals are typically supplied in PBS, pH 7.2, containing 40% glycerol with 0.02% Sodium Azide . For these preparations:

• Store at 4°C for short-term usage (up to 1 month)

• For long-term storage, aliquot and store at -20°C

• Avoid repeated freeze/thaw cycles as they can lead to protein denaturation and loss of activity

• When working with lyophilized antibody formulations, reconstitute with PBS (pH 7.3) to achieve a final antibody concentration of approximately 1 mg/mL

• For carrier-free antibodies intended for conjugation experiments, perform an additional round of desalting after reconstitution

Following these guidelines will help preserve antibody functionality and experimental reproducibility.

How can N4BP2L2 antibodies be applied in studying neutropenia disorders?

N4BP2L2's interaction with neutropenia-associated proteins makes it a valuable target for investigating neutropenia disorders through these methodological approaches:

• Protein-protein interaction studies: Use co-immunoprecipitation with N4BP2L2 antibodies to analyze interactions with Gfi-1 and Neutrophil Elastase in bone marrow samples from neutropenia patients versus controls

• Expression profiling: Quantify N4BP2L2 protein levels via Western blotting in response to arsenic exposure, as dramatic down-regulation of N4BP2L2 precedes neutropenia development

• Phosphorylation analysis: Employ phospho-specific antibodies alongside total N4BP2L2 antibodies to monitor Ser 199 phosphorylation status following DNA damage

• Cellular localization: Use immunofluorescence with N4BP2L2 antibodies to track protein redistribution in response to stress stimuli

This multifaceted approach can provide insights into the molecular mechanisms connecting N4BP2L2 dysfunction with neutropenia pathophysiology, particularly in cases related to ELA2 gene defects which cause cyclic hematopoiesis with decreased circulating neutrophils .

What is the role of circ-N4BP2L2 in cancer research and how can antibodies help investigate this?

Recent research has revealed that circular RNA N4BP2L2 (circ-N4BP2L2) plays a significant role in non-small cell lung cancer (NSCLC). Investigators can utilize N4BP2L2 antibodies in this context through these methodological approaches:

• Expression correlation studies: Combine RNA detection methods (for circ-N4BP2L2) with protein analysis using N4BP2L2 antibodies to establish relationships between circular RNA and protein expression

• Functional pathway analysis: After circ-N4BP2L2 knockdown or overexpression, use N4BP2L2 antibodies to analyze downstream protein changes in the miR-135a-5p/ARL5B axis

• Mitochondrial function assessment: Employ fractionation techniques followed by immunoblotting with N4BP2L2 antibodies to evaluate protein localization in mitochondrial versus nuclear compartments

• In vivo validation: Analyze tumor xenografts with differentially expressed circ-N4BP2L2 using immunohistochemistry with N4BP2L2 antibodies

Evidence shows that circ-N4BP2L2 enhances NSCLC progression via the miR-135a-5p/ARL5B axis, contributing to malignant phenotypes and affecting mitochondrial function . Understanding these mechanisms could identify novel therapeutic targets for NSCLC treatment.

How can researchers validate N4BP2L2 antibody specificity for their experimental systems?

Rigorous validation of N4BP2L2 antibody specificity is essential for experimental reliability. Implement this comprehensive validation protocol:

• Positive and negative controls: Include known positive tissues (e.g., bone marrow) and negative controls (tissues with minimal N4BP2L2 expression)

• Knockdown/knockout validation: Compare antibody signal in wild-type cells versus cells with CRISPR/siRNA-mediated N4BP2L2 reduction

• Protein array testing: Validate against protein arrays containing N4BP2L2 alongside non-specific proteins (similar to verification performed for commercial antibodies against 383 non-target proteins)

• Multiple antibody comparison: Use both monoclonal and polyclonal antibodies targeting different epitopes of N4BP2L2 to confirm consistent detection patterns

• Western blot molecular weight confirmation: Verify detection of the expected ~65 kDa band corresponding to the 583 amino acid N4BP2L2 protein

• Mass spectrometry validation: Perform immunoprecipitation followed by mass spectrometry to confirm pulled-down protein identity

This multi-parameter validation approach ensures experimental results truly reflect N4BP2L2 biology rather than non-specific antibody interactions.

What are the optimal conditions for Western blot analysis using N4BP2L2 antibodies?

For successful Western blot detection of N4BP2L2, follow this optimized protocol:

• Sample preparation:

  • Use RIPA buffer supplemented with protease and phosphatase inhibitors

  • Include DTT (1mM) to maintain reducing conditions for optimal epitope exposure

• Gel electrophoresis and transfer:

  • Load 20-50μg total protein per lane

  • Use 8-10% polyacrylamide gels to adequately resolve the 65kDa N4BP2L2 protein

  • Transfer to PVDF membrane at 25V overnight at 4°C for complete transfer of larger proteins

• Blocking and antibody incubation:

  • Block with 5% non-fat milk in TBST for 1 hour at room temperature

  • For monoclonal antibodies (OTI3G7 or OTI7F5), dilute 1:1000 in blocking buffer

  • Incubate primary antibody overnight at 4°C with gentle rocking

• Detection optimization:

  • Use HRP-conjugated secondary antibodies with enhanced chemiluminescence

  • For low abundance samples, consider enhanced sensitivity substrates or signal amplification systems

This protocol has been validated with both monoclonal antibodies (OTI3G7, OTI7F5) for human samples and may require minor adjustments for different experimental systems .

How can researchers investigate N4BP2L2 phosphorylation states effectively?

To study phosphorylation of N4BP2L2, particularly at Ser 199 which responds to DNA damage, implement this specialized workflow:

• Stimulation conditions:

  • Treat cells with DNA damaging agents (e.g., UV, ionizing radiation, genotoxic chemicals)

  • Include ATM/ATR inhibitors in parallel samples to confirm kinase involvement

• Sample preparation:

  • Use phosphatase inhibitor-enriched lysis buffers (sodium orthovanadate, sodium fluoride, β-glycerophosphate)

  • Perform phosphoprotein enrichment via metal oxide affinity chromatography if studying low abundance samples

• Detection methods:

  • Use phospho-specific antibodies when available

  • Employ Phos-tag™ acrylamide gels to separate phosphorylated from non-phosphorylated forms

  • Confirm phosphorylation with lambda phosphatase treatment of control samples

• Validation approaches:

  • Perform immunoprecipitation with total N4BP2L2 antibodies followed by phosphoserine detection

  • For comprehensive mapping, use mass spectrometry after enrichment

This methodology allows researchers to track N4BP2L2 phosphorylation dynamics in response to DNA damage and other cellular stresses, providing insight into its regulatory mechanisms .

What strategies can overcome common technical challenges when working with N4BP2L2 antibodies?

Researchers frequently encounter technical challenges when working with N4BP2L2 antibodies. Implement these evidence-based solutions:

• High background signal:

  • Increase blocking duration to 2 hours using 5% BSA instead of milk

  • Add 0.1-0.3% Triton X-100 to antibody dilution buffer to reduce non-specific binding

  • For immunofluorescence, include an extra blocking step with 10% serum from secondary antibody host species

• Weak detection signal:

  • For reconstituted lyophilized antibodies, verify concentration after reconstitution

  • Optimize antibody concentration through titration experiments

  • Consider signal amplification systems like tyramide signal amplification

  • For monoclonal antibodies, try epitope retrieval approaches if working with fixed tissues

• Inconsistent results between experiments:

  • Aliquot antibodies upon receipt to avoid freeze-thaw degradation

  • Standardize protein extraction methods and quantification

  • Include internal loading controls and positive control samples in each experiment

  • Document lot numbers as epitope recognition can vary between manufacturing batches

These technical optimizations significantly improve experimental reproducibility and data reliability when studying N4BP2L2.

How can N4BP2L2 antibodies be applied in studying its role in the miR-135a-5p/ARL5B regulatory axis?

Recent findings on circ-N4BP2L2's function in regulating the miR-135a-5p/ARL5B axis present opportunities for mechanistic investigations using these methodological approaches:

• Co-localization studies:

  • Perform dual immunofluorescence using N4BP2L2 antibodies alongside ARL5B antibodies

  • Combine with RNA fluorescence in situ hybridization (FISH) for miR-135a-5p detection

  • Analyze subcellular distribution patterns in normal versus cancer cells

• Functional interaction analysis:

  • Use proximity ligation assay (PLA) to detect protein-protein interactions in situ

  • Following circ-N4BP2L2 modulation, track changes in N4BP2L2 protein levels via Western blot

  • Perform RNA immunoprecipitation with N4BP2L2 antibodies to identify associated RNA species

• Signal pathway mapping:

  • Create experimental conditions with stable circ-N4BP2L2 overexpression or knockdown

  • Use phospho-specific antibodies to track activation states of downstream effectors

  • Employ protein arrays to identify novel interaction partners in the regulatory network

This integrated approach can elucidate how circ-N4BP2L2 influences mitochondrial function and cancer progression through this regulatory axis, potentially revealing new therapeutic targets.

What is the relationship between N4BP2L2 and cancer progression, and how can researchers investigate this?

The connection between N4BP2L2 and cancer progression, particularly in NSCLC, can be investigated through these methodological approaches:

• Expression correlation analysis:

  • Perform immunohistochemistry on tissue microarrays containing normal lung and NSCLC tissues at different stages

  • Quantify N4BP2L2 protein levels via Western blot across cancer cell lines with varying invasive potential

  • Correlate protein expression with patient survival data and clinical parameters

• Functional studies:

  • Conduct gain/loss-of-function experiments using stable cell lines

  • Assess changes in proliferation, invasion, apoptosis, and mitochondrial function

  • Use N4BP2L2 antibodies to confirm successful manipulation of protein levels

• Mechanistic investigation:

  • Perform chromatin immunoprecipitation (ChIP) with N4BP2L2 antibodies to identify regulated genes

  • Analyze posttranslational modifications using specific antibodies or mass spectrometry

  • Investigate protein interactions unique to cancer contexts through co-immunoprecipitation

Recent evidence indicates that circular RNA forms of N4BP2L2 enhance NSCLC progression by influencing mitochondrial function, suggesting the protein itself may have related functions in cancer biology that warrant further investigation .

What are the current knowledge gaps and future research directions for N4BP2L2 antibody applications?

Despite significant advances in understanding N4BP2L2 biology, several knowledge gaps remain that represent important opportunities for future research:

• Comprehensive epitope mapping of commercially available antibodies would improve application-specific selection and cross-reactivity understanding

• Development of phospho-specific antibodies targeting Ser 199 would facilitate direct monitoring of this modification following DNA damage

• Validation across diverse experimental systems beyond established cell lines, particularly in primary patient-derived samples

• Creation of multiplexed detection systems combining N4BP2L2 with interacting partners like Gfi-1 and Neutrophil Elastase

• Standardized protocols for challenging applications such as ChIP-seq or single-cell protein detection methods

The continuing development of more specific and sensitive antibodies against N4BP2L2, along with optimized methodologies, will enable researchers to further elucidate this protein's roles in neutropenia, cancer progression, and other biological contexts .

How can researchers contribute to improved N4BP2L2 antibody development and validation?

The research community can advance N4BP2L2 antibody development and validation through these practical approaches:

• Systematic cross-validation studies comparing different antibodies across standardized experimental conditions

• Public repository contributions of validation data, including negative results and application-specific optimizations

• Development of engineered cell lines expressing tagged versions of N4BP2L2 to serve as definitive positive controls

• Collaboration with commercial providers to test new antibody formulations against researcher-established validation criteria

• Implementation of emerging antibody technologies such as recombinant antibodies with defined binding characteristics