Active Recombinant Human Topoisomerase (DNA) I, C-terminal Domain

• Cat.No.: TOP1-1196H

Specification

• Cat. No.: TOP1-1196H
• Description: Human DNA Topoisomerase I catalyzes the relaxation of both positive and negative supercoils without the requirement of energy. In addition to DNA replication and transcriptional activation, DNA Topoisomerase I also plays a major role in pre-mRNA splicing, recombination, chromatin remodeling, and other DNA or RNA templating activities. The C-terminal domain of DNA Topoisomerase I expanded from amino acids 713 to 765 is highly conserved and connected to the core domain by a poorly conserved linker domain (residues 636-713). An active site tyrosine has been characterized at position 723. Mutation from tyrosine to phenylalanine at position 723 preferentially binds the supercoiled DNA rather than relaxed DNA in the mixture of supercoiled and relaxed DNAs. The C-terminal domain of DNA Topoisomerase I protein (residues 651-765) was expressed in baculovirus system and purified by using an affinity column and FPLC chromatography. Purified Topo I CTD can be reconstituted with the core domain forin vitroDNA relaxation assay. Purified Topo I protein (CTD) is greater than 95% homogeneous and contains no detectable protease, DNase, and RNase activity.
• Source: Sf9 insect cells.
• Form: Liquid. Supplied in 20 mM Tris-HCl, pH 8.0, 100 mM KCl, 0.2 mM EDTA, 1 mM DTT, 20 % glycerol.
• Purity: > 95% by SDS-PAGE.
• Activity: 1-10 ng of Topo I CTD can be reconstituted with core domain to restore DNA relaxation activity and contains no detectable DNA relaxation activity by itself.
• Usage: For in vitro use only.
• Storage: Quality guaranteed for 12 months store at -80°C. Avoid freeze / thaw cycles.
• Tag: Non

Gene Information

• Gene Name: TOP1 topoisomerase (DNA) I [ Homo sapiens ]
• Synonyms: TOP1; topoisomerase (DNA) I; TOPI; DNA topoisomerase1; EC 5.99.1.2; OTTHUMP00000031713; DNA topoisomerase I; topoisomerase I; type I DNA topoisomerase
• Gene ID: 7150
• mRNA Refseq: NM_003286
• Protein Refseq: NP_003277
• MIM: 126420
• UniProt ID: P11387
• Chromosome Location: 20q12-q13.1
• Function: ATP binding; DNA topoisomerase (ATP-hydrolyzing) activity; DNA topoisomerase type I activity; chromatin binding; nucleotide binding; protein binding

Reviews

10/17/2019

Accurate protein structural analysis; a key for structural biology.

10/06/2018

High-quality protein crystallography; essential for structural biology.

05/30/2018

Timely protein characterization; vital for our research projects.

Q&As

What is the role of TOP1 in the repair of DNA damage caused by environmental factors and chemotherapeutic agents?

TOP1 repairs DNA damage, maintaining genomic stability under stress.

How do post-translational modifications of TOP1, such as phosphorylation, affect its enzymatic activity and interaction with DNA?

Post-translational modifications like phosphorylation affect TOP1's activity and DNA interaction.

How do mutations in the TOP1 gene contribute to genomic instability and the development of certain cancers?

Mutations in TOP1 cause genomic instability, increasing cancer risk.

What are the effects of TOP1 inhibitors on cancer cell proliferation and survival?

TOP1 inhibitors lead to cancer cell death and inhibit tumor growth by disrupting DNA processes.

How does TOP1 interact with other proteins in the DNA repair and replication machinery?

TOP1 works with other DNA repair proteins, ensuring accurate DNA synthesis.

How does TOP1 regulate DNA unwinding and re-ligation during transcription and replication?

TOP1 regulates DNA unwinding by creating transient breaks, aiding transcription and replication.

What are the implications of TOP1 expression levels in predicting the response to chemotherapy in cancer patients?

TOP1 expression levels predict chemotherapy responses in cancer treatment.