Sigma-Aldrich Anti-Rpa1 Clone 1J5 Zoomab Rb Mono

Replication protein A 70 kDa DNA-binding subunit (UniProt: P27694; also known as RP-A p70, Replication factor A protein 1 (RF-A protein 1), Single-stranded DNA-binding protein) is encoded by the RPA1 (also known as REPA1, RPA70) gene (Gene ID: 6117) in human. It plays a pivotal role in the DNA replication, repair, and recombination. It also participates in the transcriptional regulation of various genes. RPA70 is ubiquitously expressed in various tissues, with higher expression levels observed in proliferating cells. It is primarily localized in the nucleus, where it associates with sites of DNA replication and repair. It can also be found in the nucleoplasm and at the sites of DNA damage. RPA1 protein is cleaved into N-terminally processed chain, and is the largest component (70kDa) of the heterotrimeric complex RPA with three three subunits: RPA70, RPA32, and RPA14. RPA70 is characterized by a central DNA-binding domain that enables it to interact with single-stranded DNA (ssDNA). Its zinc finger domain (aa 481-503) binds to the single-stranded DNA to form the RPA holocomplex. In addition, it also helps to unwind the double strand, stimulates DNA polymerases and , and form the initial short Okazaki fragments. At the damage site, RPA1 recruits DNA double-strand break repair factors, RAD51 and RAD52 to the chromatin. RPA1 is known to influence cell cycle through CDK4/Cyclin-D pathway. Acetylation status of RPA1 played a crucial role in repair of DNA damage via nucleotide excision repair. Alterations in RPA70 expression have been associated with Pulmonary fibrosis, neurodegenerative diseases and certain genetic disorders that affect DNA repair mechanisms. Studies report Rpa1 knockout mice develop fatty liver and hepatocellular carcinoma. RPA1 is required for the transcription of genes involved in lipid metabolism. RPA1 is significantly up-regulated in hepatocellular carcinoma and correlates with poor prognosis. This ZooMAb^® recombinant monoclonal antibody, generated by our proprietary technology, offers significantly enhanced specificity, affinity, reproducibility, and stability over conventional monoclonals. (Ref.: Yin, Q., et Al., (2022). Cell Reports. 40(2);111071; Algethami, M., et Al. (2023). npj breast cancer. 9:(18).

We are committed to bringing you greener alternative products, which adhere to one or more of the 12 Principles of Green Chemistry. This antibody is preservative-free, produced without the harm or sacrifice of animals and exceptionally stable to allow for ambient shipping and storage if needed, and thus aligns with "Waste Prevention", "Designing Safer Chemicals" and "Design for Energy Efficiency". Click here for more information.

ZooMAb^® antibodies represent an entirely new generation of recombinant monoclonal antibodies. Each ZooMAb^® antibody is manufactured using our proprietary recombinant expression system, purified to homogeneity, and precisely dispensed to produce robust and highly reproducible lot-to-lot consistency. Only top-performing clones are released for use by researchers. Each antibody is validated for high specificity and affinity across multiple applications, including its most commonly used application. ZooMAb^® antibodies are reliably available and ready to ship when you need them.

KLH-conjugated linear peptide corresponding to 21 amino acids from the N-terminal half of human RPA1.

Quality Control Testing

Evaluated by Western Blotting in lysate from NIH/3T3 cells.


Western Blotting Analysis: A 1:10,000 dilution of this antibody detected RPA1 in NIH/3T3 cell lysate.

Tested Applications

Western Blotting Analysis: A 1:1,000-10,000 dilution from a representative lot detected RPA1 in nuclear extracts from Jurkat cells, C6 cells, and HeLa cells.

Immunocytochemistry Analysis: A 1:100 dilution from a representative lot detected RPA1 in HeLa cells.

Affinity Binding Assay: A representative lot of this antibody bound RPA1 peptide with at least one thousand-fold (1,000X) higher affinity than with non-specific control peptide.

Flow Cytometry Analysis: 1 µg from a representative lot detected RPA1 in one million Raji cells.

Immunohistochemistry (Paraffin) Analysis: A 1:100 dilution from a representative lot detected RPA1 in human gastric cancer and human testis cancer tissue sections.

Note: Actual optimal working dilutions must be determined by end user as specimens, and experimental conditions may vary with the end user.

Clone 1J5 is a ZooMAb^® recombinant rabbit monoclonal antibody that specifically detects RPA1. It targets an epitope within 21 amino acids from the N-terminal half.

Purified recombinant rabbit monoclonal antibody IgG, lyophilized in PBS with 5% Trehalose, normal appearance a coarse or translucent resin. The PBS/trehalose components in the ZooMAb formulation can have the appearance of a semi-solid (bead like gel) after lyophilization. This is a normal phenomenon. Please follow the recommended reconstitution procedure in the data sheet to dissolve the semi-solid, bead-like, gel-appearing material. The resulting antibody solution is completely stable and functional as proven by full functional testing. Contains no biocide or preservatives, such as azide, or any animal by-products. Larger pack sizes provided as multiples of 25 µL.

300 µg/mL after reconstitution at 25 µL per vial. Please refer to guidance on suggested starting dilutions and/or titers per application and sample type.

Recommend storage of lyophilized product at 2-8°C; Before reconstitution, micro-centrifuge vials briefly to spin down material to bottom of the vial; Reconstitute each vial by adding 25 µL of filtered lab grade water or PBS; Reconstituted antibodies can be stored at 2-8°C, or -20°C for long term storage. Avoid repeated freeze-thaws.

ZooMAb is a registered trademark of Merck KGaA, Darmstadt, Germany

Unless otherwise stated in our catalog or other company documentation accompanying the product(s), our products are intended for research use only and are not to be used for any other purpose, which includes but is not limited to, unauthorized commercial uses, in vitro diagnostic uses, ex vivo or in vivo therapeutic uses or any type of consumption or application to humans or animals.