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

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.

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).

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

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.

90.7 kDa calculated.

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.

Concentration: Please refer to lot specific datasheet.

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