Phospho-Histone H2AX Antibody (pS139)

Overview

Phospho-Histone H2AX Antibody (pS139) is a research-use antibody directed against PHOSPHO-HISTONE H2AX. It is supplied for use in common immunoassay contexts such as IHC-P, IF/ICC, WB (RUO).

Key elements and design rationale

• Target: PHOSPHO-HISTONE H2AX.
• Description (provided): Variant histone H2A which replaces conventional H2A in a subset of nucleosomes.
• Antibody type: Rabbit, clone AbH41, Rabbit IgG.
• Format: Purified; Protein A affinity.
• Reported/predicted localization: Nucleus.
• Species reactivity: tested: Human, Mouse.
• Immunogen (if provided): The amino acids surrounding a phosphorylated serine at position 139 were used as the immunogen for the phospho-Histone H2AX antibody..

The information above helps you match the antibody format to your assay context, interpret species-dependent differences, and anticipate how epitope context (isoforms, PTMs, or conformational state) may influence signal.

Biological background

Variant histone H2A which replaces conventional H2A in a subset of nucleosomes. Nucleosomes wrap and compact DNA into chromatin, limiting DNA accessibility to the cellular machineries which require DNA as a template. Histones thereby play a central role in transcription regulation, DNA repair, DNA replication and chromosomal stability. DNA accessibility is regulated via a complex set of post-translational modifications of histones, also called histone code, and nucleosome remodeling. Required for checkpoint-mediated arrest of cell cycle progression in response to low doses of ionizing radiation and for efficient repair of DNA double strand breaks (DSBs) specifically when modified by C- terminal phosphorylation. [UniProt]

For curated annotations (gene/protein naming, domains, isoforms, and pathway links) for PHOSPHO-HISTONE H2AX, consult primary databases such as UniProt, NCBI Gene, and Ensembl.

Research relevance and current trends

• Context-dependent expression studies: researchers often examine PHOSPHO-HISTONE H2AX abundance and localization across perturbations (genetic, pharmacologic, or environmental) to connect phenotype to molecular changes.
• Reagent reproducibility: there is growing emphasis on antibody specificity checks using orthogonal approaches (e.g., genetic perturbation or independent antibodies) and transparent reporting of clone/lot information.
• Multi-modal datasets: antibody-based readouts are increasingly combined with transcriptomics and imaging to relate protein-level measurements to cell-state transitions.

Common research applications

• Immunohistochemistry for spatial mapping of target expression across tissues and cell types.
• Immunofluorescence for subcellular localization and cell-type specific expression patterns.
• Western blotting (immunoblot) for relative detection of target protein abundance and apparent molecular weight.

When comparing conditions, interpret changes in signal in the context of sample composition, expected localization, and any known isoform complexity for the target.

Notes for experimental interpretation

• Isoforms and PTMs: alternative splicing or post-translational modifications can change epitope accessibility and apparent molecular weight; interpret bands/signals accordingly.
• Cross-reactivity and matrix effects: background binding can vary by sample type, species, and blocking/detection chemistries; include appropriate negative controls.
• Control concepts: where feasible, use genetic perturbation (KO/KD/overexpression), orthogonal assays, or independent antibodies to support specificity claims.

Antibody considerations: Polyclonal reagents may recognize multiple epitopes and can increase sensitivity but may show broader binding profiles, while monoclonal clones provide a single-epitope readout that can improve consistency across experiments. If a conjugate is listed, the antibody supports more direct detection workflows; otherwise, it is typically used with a compatible secondary antibody.

Customization & Add-ons: Can’t find the antibody you need—or require a custom format for your assay? We can help you source the best match or support custom antibody solutions for diverse research needs, including species and isotype selection, conjugations and labeling (e.g., HRP/AP, biotin, fluorophores), purification grade options (Protein A/G, affinity purified), formulation preferences (buffer selection, carrier-free, glycerol-free), custom concentrations and aliquoting, low-endotoxin options for cell-based work, and application-focused QC/validation support (project dependent). Click Talk to a Scientist to submit a request, email us at support@biohippo.com, or explore our Research Services for additional support—our team will follow up with feasibility details and next steps.