Phospho-RNA polymerase II Antibody (pS5) / POLR2A

Overview

RNA polymerase II (Pol II) is an enzyme that is composed of 12 subunits and is responsible for the transcription of protein-coding genes. Transcription initiation requires Pol II-mediated recruitment of transcription machinery to a target promoter, thereby allowing transcription to begin. The largest subunit of Pol II (referred to as RPB1 or RPB205) is a 1,840 amino acid protein that contains one C2H2-type zinc finger and a C-terminal domain comprised of several heptapeptide repeats. Although Pol II function requires the cooperation of all twelve subunits, the largest subunit conveys Pol II catalytic activity and, together with the second largest subunit, forms the active center of the Pol II enzyme. Additionally, the large subunit participates in forming the DNA-binding domain of Pol II, a groove that is necessary for transcription of the DNA template. Without proper function of the large subunit, mRNA synthesis and subsequent transcription elongation cannot occur.

This anti-POLR2A (pS5) antibody is supplied as Purified (Mouse, Monoclonal (mouse origin), clone CTD 8A7, Mouse IgM, kappa, Unconjugated) and is designed to support common target-detection workflows after the on-page specifications.

Key elements and design rationale

• Target: POLR2A (pS5)
• Format: Purified
• Localization: Nuclear
• Species reactivity: Human
• Applications (listed): FACS, IF, WB, IHC-P
• Conjugate: Unconjugated
• Clone and antibody class: Monoclonal (mouse origin), clone CTD 8A7, Mouse IgM, kappa

Because antibody performance can depend on epitope context, sample preparation, and biological state, interpret signals using appropriate controls and orthogonal evidence when possible.

Biological background

POLR2A (pS5) is referenced in public gene/protein resources (e.g., UniProt and NCBI Gene), which provide curated names/synonyms, protein features, and pathway context. When designing assays, consider potential isoforms, post-translational modifications, and cell-type specific expression that may influence observed signal.

Research relevance and current trends

• Profiling POLR2A (pS5) expression across model systems, perturbations, and time points to support mechanistic hypotheses.
• Combining antibody-based detection with multi-omics or imaging readouts to link POLR2A (pS5) signal with phenotype.
• Using well-matched controls (isotype controls, genetic perturbations, or independent reagents) to strengthen interpretation of target-associated signal.

Common research applications

• FACS
• IF
• WB
• IHC-P

Use the listed applications as a starting point and tailor experimental design to your sample type and readout requirements.

Notes for experimental interpretation

• Specificity considerations: closely related family members, isoforms, or PTMs can affect apparent specificity; confirm with independent approaches when critical.
• Controls: include negative controls and, when feasible, genetic or pharmacologic perturbations to support target attribution in your system.
• Species and sample context: differences in sequence, expression, fixation, or extraction conditions can change signal behavior across models.

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.