| Field | Specification |
|---|---|
| Target | |
| Alternative names | DNA-directed RNA polymerase I subunit RPA2; RNA polymerase I subunit 2; DNA-directed RNA polymerase I 135 kDa polypeptide; RPA135; POLR1B |
| UniProt # | |
| Host | |
| Clonality | |
| Isotype | |
| Reactivity | |
| Applications | |
| Immunogen | E.coli-derived human POLR1B recombinant protein (Position: H18-V1135). |
| Molecular weight | |
| Purification | |
| Reconstitution | |
| Cellular localization | |
| Concentration | |
| Form | Lyophilized |
| Storage | |
| Catalog no. (Mfr.) | |
| Main SKU |
Product Overview
This rabbit polyclonal antibody recognizes DNA-directed RNA polymerase I subunit RPA2 (gene POLR1B) in human samples and is validated for Western blot, IHC, ICC/IF, flow cytometry and ELISA. The predicted molecular weight is 128.2 kDa, and the supplier reports an observed band at about 128 kDa.
POLR1B (RPA135) is the second-largest subunit of RNA polymerase I and forms part of its catalytic core together with POLR1A. Pol I transcribes the ribosomal DNA repeats to produce the 47S pre-rRNA, the precursor of most ribosomal RNA. POLR1B is studied in nucleolar function and ribosome biogenesis.
| Target | DNA-directed RNA polymerase I subunit RPA2 (gene POLR1B; UniProt Q9H9Y6, human) |
|---|---|
| Host / Clonality / Isotype | Rabbit / Polyclonal / Rabbit IgG |
| Reactivity | Human |
| Form | Lyophilized |
| Formulation | Per vial: 4 mg trehalose; 0.9 mg NaCl; 0.2 mg Na2HPO4 |
| Calculated MW | 128.2 kDa |
| Observed MW | 128 kDa |
| Storage | As supplied: −20 °C for up to 12 months from receipt. After reconstitution: 4 °C for up to 1 month, or aliquot and keep at −20 °C for up to 6 months. Avoid repeated freeze–thaw cycles. |
Validated Applications
| Western blot | 0.25–0.5 µg/mL (Human) |
|---|---|
| IHC (paraffin sections) | 2–5 µg/mL (Human) |
| Immunocytochemistry / Immunofluorescence | 5 µg/mL (Human) |
| Flow cytometry (fixed cells) | 1–3 µg/1x1×106 cells (Human) |
| ELISA | 0.1–0.5 µg/mL |
Samples with a confirmed band (WB): human K562 cells, human HepG2 cells, human 293T cells.
Recommended loading (WB): 20–40 µg of total protein per lane.
Conditions in the example images (WB): 5–20% gradient SDS-PAGE under reducing conditions, 30 µg lysate per lane, transfer to nitrocellulose membrane, blocking in 5% non-fat milk, primary antibody at 0.5 µg/mL overnight at 4 °C, HRP-conjugated secondary antibody at 1:5000, ECL detection.
Samples with confirmed staining (IHC): human breast cancer tissue, human lymphoma tissue.
Recommended antigen retrieval: heat-mediated, in TE buffer (pH 9.0); citrate buffer (pH 6.0) can be used instead.
Conditions in the example images (IHC): heat-mediated antigen retrieval in EDTA buffer (pH 8.0).
Samples with confirmed staining (ICC/IF): PC-3 cells.
Samples with a confirmed signal (flow cytometry): A431 cells.
Immunogen
Recombinant human POLR1B fragment (His18–Val1135), expressed in E. coli.
Reactivity Notes
The supplier lists reactivity with human. UniProt places DNA-directed RNA polymerase I subunit RPA2 in the nucleus and chromosome. The samples tested by the supplier (listed above) are a practical starting point for positive controls.
Safety
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.
