These HR/NHEJ kits are cell based, meaning they have the HR or NHEJ GFP reporters pre-installed. A single plasmid (I-Sce1) is transfected to activate repair. Please see this table for a summary and comparison/application of each kit.
Homologous GFP Repair Systems
HeLa Cell HR Kit (I-Sce1 Based)
HeLa Cell HR Kit (CRISPR-CAS Based)
Human Neuroblastoma Cell Line SH-SY5Y using (I-Sce1 transfection)
Mouse 3T3 Cell Line using I-Sce1 transfection
Mouse Neuronal Cell Line using I-Sce1 transfection
Custom construction Kit to make your own HR Cell Reporter
NHEJ GFP Reporter
Systems
Transfection-based HR and NHEJ kits use transient transfections to make a pool of cells containing the DNA reporters to allow the investigator to interrogate the 2 major DNA repair pathways. The advantages are:
A newly published study in Molecular Cell highlights an exciting advance in topoisomerase biology and potential cancer therapeutics. Importantly, this work was enabled using topoisomerase reagents and assay technologies supplied by TopoGEN. Konada and colleagues report that Heat Shock Factor 1 (HSF1) selectively stimulates the catalytic activity of DNA topoisomerase IIβ (TOP2β) while exerting minimal effects on […]
A new study published in Nature Structural & Molecular Biology provides important insights into how cells repair DNA damage arising from collapsed replication forks—one of the most significant threats to genome stability and a key driver of cancer, aging, and genetic disease. The authors demonstrate that repair outcomes differ dramatically depending on whether a single replication fork […]
A newly published study in Scientific Reports describes the identification and characterization of alternariol monomethyl ether (AME), a fungal secondary metabolite isolated from Alternaria alternata, with potent antiproliferative activity linked to inhibition of both DNA Topoisomerase I and II. Importantly, the investigators utilized TopoGEN’s plasmid relaxation and kDNA decatenation assay systems to quantify enzyme inhibition kinetics and demonstrate […]
There is an increasingly important enabling technology in gene therapy and nucleic acid delivery: the use of DNA Gyrase to generate highly supercoiled plasmid DNA, a topology that is strongly correlated with improved delivery efficiency and functional expression and enhanced efficiency in gene therapy.
Recent work published in Geroscience highlights an unexpected connection between topoisomerase inhibitors and longevity biology.
A new Phytomedicine (2026) study caught my attention—not because it shows anti-melanoma activity (we’ve seen that before), but because it begins to unpack how a plant-derived formulation enhances the efficacy of temozolomide (TMZ).
A newly published study in the Journal of Molecular Biology (2026) provides important mechanistic insight into how tyrosyl-DNA phosphodiesterase I (Tdp1) processes topoisomerase-mediated DNA damage—extending its functional relevance beyond its classical role in Top1 repair and into the Top2 space.
A new publication in the European Journal of Medicinal Chemistry reports a surprising and important discovery about how certain gold(III) compounds interact with human topoisomerase IIα (Top2α)—and the work was made possible using TopoGEN products.
A groundbreaking new Nature study reveals that cancer cells use specialized genomic “retention elements” to preserve and propagate extrachromosomal circular DNA (ecDNA)—a major engine of oncogene amplification and tumor evolution. These circular ecDNAs, which lack centromeres and segregate randomly, should theoretically be lost at each cell division. Yet this work shows that cancer cells have evolved a mechanism […]
A major Cell paper has uncovered a completely new layer of DNA repair biology: cells use selective autophagy and lysosomes to process and remove Topoisomerase I cleavage complexes (TOP1cc)—the toxic DNA–protein crosslinks created during normal replication and when cells are exposed to TOP1-targeting drugs like camptothecin. According to the Cell article (2024), researchers discovered that: […]
