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bioRxiv · 10.1101/2020.02.29.971317

An Improved 4'-Aminomethyltroxsalen-Based DNA Crosslinker for Biotinylation of DNA

Wielenberg, K.·Wang, M.·Yang, M.·Ozer, A.·Lis, J.·Lin, H.
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Abstract

Nucleic acid crosslinkers that covalently join commentary strands have applications as both pharmaceuticals and biochemical probes. Psoralen is a popular crosslinker moiety that reacts with double stranded DNA and RNA upon irradiation with long wave UV light. A commercially available compound EZ-Link Psoralen-PEG3-Biotin has been used in many studies to crosslink DNA and double strand RNA for genome-wide investigations. Here we present a novel probe, AP3B, which uses a psoralen derivative, 4-aminomethyltrioxsalen, to biotinylate nucleic acids. We show that this compound is 8-fold more effective at labeling DNA in cells and several hundred-fold more effective at crosslinking two strands of DNA in vitro than the commercially available compound EZ-Link Psoralen-PEG3-Biotin.

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Wielenberg, K., Wang, M., Yang, M., Ozer, A., Lis, J., Lin, H.. 2020-02-29. An Improved 4'-Aminomethyltroxsalen-Based DNA Crosslinker for Biotinylation of DNA. https://doi.org/10.1101/2020.02.29.971317

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