Anti-Topoisomerase I-DNA Covalent Complexes Antibody, clone 1.1A

90.7 kDa calculated.

DNA topoisomerase 1 (EC 5.99.1.2; UniProt P11387; also known as DNA topoisomerase I, Topo I) is encoded by the TOP1 (also known as TOPI) gene (Gene ID 7150) in human. Topo I relaxes double strand DNA (dsDNA) torsional strain by nicking one strand of the dsDNA to allow rotation of the nicked 3′-hydroxy end around the unnicked strand, while the 5′-phosphoryl end of the nicked DNA forms a covalent phosphodiester bond with a tyrosine residue on Topo I. The nicked 3′-hydroxy end then attacks the DNA-enzyme phosphoester bond to religate the nicked DNA strand. One supercoil is removed during each round of Topo I-catalyzed nicking and resealing. Camptothecins are widely used for cancer treatment, these drugs intercalate into DNA at the topo I active site, inhibiting the religation step of the enzyme and shifting the equilibrium toward covalent topo I-DNA complexes rather than free topo I and DNA. Interaction of these drug-stabilized covalent topo I-DNA complexes with advancing replication forks or transcription complexes causse further DNA damage and eventual cell death.

Epitope: Topo I pTyr723.

KLH-conjugated linear peptide corresponding to human Topo I target site sequence with phosphorylated Tyr723.

Anti-Topoisomerase I-DNA Covalent Complexes Antibody, clone 1.1A is an antibody against Topoisomerase I-DNA Covalent Complexes for use in Immunocytochemistry, Flow Cytometry, Dot Blot, ELISA.

Flow Cytometry Analysis: 1.0 µg of this antibody from a representative lot detected topoisomerase I/DNA covalent complexes in Topotecan-treated HCT116 human colon cancer cells.

Immunocytochemistry Analysis: 10 µg/mL from a representative lot detected topoisomerase I/DNA covalent complexes in Topotecan-treated A549 human lung carcinoma cells (Courtesy of Dr. Scott H. Kaufmann, Mayo Clinic, Rochester, MN).

Flow Cytometry Analysis: 10 µg/mL from a representative lot detected topoisomerase I/DNA covalent complexes in Topotecan-treated HCT116 human colon cancer cells (Courtesy of Dr. Scott H. Kaufmann, Mayo Clinic, Rochester, MN).

Dot Blot Analysis: A representative lot detected the Topotecan-/TPT-stablized topoisomerase I/DNA covalent complexes, but not free topoisomerase I (non-DNA complexed) by slot blot using CsCl2 gradient-fractionated lysates from TPT-treated and untreated A549 cells (Patel, A.G., et al, (2016). 44(6):2816-2826).

Dot Blot Analysis: A representative lot detected a Topotecan (TPT) dose-dependent increase of TPT-stabilized topoisomerase I/DNA covalent complexes in lysates from TPT-treated A549 and HCT116 cells by slot blot (Patel, A.G., et al, (2016). 44(6):2816-2826).

Dot Blot Analysis: A representative lot detected stabilized topoisomerase I/DNA covalent complexes in lysates from A549 cells treated with Camptothecins (CPT, SN-38, TPT) or Indenoisoquinolines (NSC 314622, NSC 725776, NSC 743400), but not nucleoside analogues (cytarabine and gemcitabine) (Patel, A.G., et al, (2016). 44(6):2816-2826).

ELISA Analysis: A representative lot detected the immunogen peptide corresponding to topoisomerase I active site sequence with phosphorylated Tyr723, but not the peptide with non-phosphorylated Tyr273 by direct (non-sandwich) ELISA (Patel, A.G., et al, (2016). 44(6):2816-2826).

Immunocytochemistry Analysis: A representative lot detected a dose-dependent increase of non-nucleolar topoisomerase I/DNA covalent complex loci in Topotecan-/TPT-treated A549 cells, while the small number of loci in untreated cells were seen only in nucleoli (Patel, A.G., et al, (2016). 44(6):2816-2826).

Immunocytochemistry Analysis: A representative lot detected a temporally and spatially distinct nuclear loci formation of topoisomerase I/DNA covalent complexes from those of phospho-H2AX and Rad51 in Topotecan-/TPT-treated A549 cells (Patel, A.G., et al, (2016). 44(6):2816-2826).

Research Category
Epigenetics & Nuclear Function

Research Sub Category
Chromatin Biology

Clone 1.1A specifically recognizes topoisomerase I (Topo I) in DNA covalent complexes, but not non-DNA complexed, free Topo I by detecting topo I active site Tyr723 phosphorylation (Patel, A.G., et al, (2016). 44(6):2816-2826).

Format: Purified

Protein G purified.

Purified mouse IgG2bκ in buffer containing 0.1 M Tris-Glycine (pH 7.4), 150 mM NaCl with 0.05% sodium azide.

Stable for 1 year at 2-8°C from date of receipt.

Evaluated by Immunocytochemistry in Topotecan-treated A549 human lung carcinoma cells.

Immunocytochemistry Analysis: 10 µg/mL of this antibody detected topoisomerase I/DNA covalent complexes in Topotecan-treated A549 human lung carcinoma cells.

Concentration: Please refer to lot specific datasheet.

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.