| Field | Specification |
|---|---|
| Target | |
| Alternative names | Cyclin-dependent kinase inhibitor 1; CDK-interacting protein 1; Melanoma differentiation-associated protein 6; MDA-6; p21; CDKN1A; CAP20; CDKN1; CIP1; MDA6; PIC1; SDI1; WAF1 |
| UniProt # | |
| Host | |
| Clonality | |
| Isotype | |
| Reactivity | |
| Applications | |
| Immunogen | E.coli-derived human P21/CDKN1A recombinant protein (Position: M1-R140). |
| Molecular weight | |
| Purification | |
| Reconstitution | |
| Cellular localization | |
| Concentration | |
| Form | Lyophilized |
| Storage | |
| Catalog no. (Mfr.) | |
| Main SKU |
Product Overview
This rabbit polyclonal antibody recognizes cyclin-dependent kinase inhibitor 1 (gene CDKN1A) in human samples and is validated for Western blot, IHC, ICC/IF and ELISA. The predicted molecular weight is 18.1 kDa, and the supplier reports an observed band at about 21 kDa.
p21 (CDKN1A, also called p21Cip1/WAF1) is a cyclin-dependent kinase inhibitor that halts the cell cycle, mainly in G1 and G2. Its expression is strongly induced by p53 after DNA damage, and it is widely used as a marker of cell cycle arrest, DNA damage responses and cellular senescence.
| Target | Cyclin-dependent kinase inhibitor 1 (gene CDKN1A; UniProt P38936, 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 | 18.1 kDa |
| Observed MW | 21 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) |
| ELISA | 0.1–0.5 µg/mL |
Samples with a confirmed band (WB): human HeLa cells, human HepG2 cells, human MCF-7 cells, human U2OS cells, human SIHA 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 thyroid cancer tissue, human ovarian cancer 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): HeLa cells.
Immunogen
Recombinant human P21/CDKN1A fragment (Met1–Arg140), expressed in E. coli.
Reactivity Notes
The supplier lists reactivity with human. UniProt places cyclin-dependent kinase inhibitor 1 in the cytoplasm and nucleus. Tissue expression noted by UniProt (human): Expressed in all adult tissues, with 5-fold lower levels observed in the brain. 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.
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