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bioRxiv · 10.1101/2024.02.22.581598

Activity of DNA polymerase κ across the genome in human fibroblasts

Torres, M. C.·Sun, D.·Spratt, T. E.
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Abstract

DNA polymerase {kappa} (Pol {kappa}) is a specialized polymerase that has multiple cellular roles such as translesion DNA synthesis, replicating repetitive sequences, and nucleotide excision repair. We have developed a method for capturing DNA synthesized by Pol {kappa} utilizing a Pol {kappa} - specific substrate, N2-(4-ethynylbenzyl)-2'-deoxyguanosine (EBndG). After shearing of the DNA into 200-500bp lengths, the EBndG-containing DNA was covalently bound to biotin using the Cu(I)- catalyzed alkyne-azide cycloaddition reaction, and isolated with streptavidin beads. Isolated DNA was then ligated to adaptors, followed by PCR amplification and next-generation sequencing (NGS) to generate genome-wide repair maps. We have termed this method polymerase {kappa} sequencing (polK-seq). Here we present the human genome maps for pol {kappa} activity in an undamaged cell line. We found that pol {kappa} activity was enhanced in euchromatin regions, the promoter of genes, and in DNA that is replicated early in S-phase.

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Torres, M. C., Sun, D., Spratt, T. E.. 2024-02-23. Activity of DNA polymerase κ across the genome in human fibroblasts. https://doi.org/10.1101/2024.02.22.581598

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