Evaluation of UDP-GlcN Derivatives for Selective Labeling of 5-(Hydroxymethyl)cytosine
Article first published online: 17 SEP 2013
Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Volume 14, Issue 16, pages 2144–2152, November 4, 2013
How to Cite
Dai, N., Bitinaite, J., Chin, H.-G., Pradhan, S. and Corrêa, I. R. (2013), Evaluation of UDP-GlcN Derivatives for Selective Labeling of 5-(Hydroxymethyl)cytosine. ChemBioChem, 14: 2144–2152. doi: 10.1002/cbic.201300294
- Issue published online: 25 OCT 2013
- Article first published online: 17 SEP 2013
- Manuscript Received: 7 MAY 2013
- New England Biolabs, Inc.
- chemical labeling;
5-(hydroxymethyl)cytosine (5-hmC) is a newly identified oxidative product of 5-methylcytosine (5-mC) in the mammalian genome, and is believed to be an important epigenetic marker influencing a variety of biological processes. In addition to its relatively low abundance, the fluctuation of 5-hmC levels over time during cell development poses a formidable challenge for its accurate mapping and quantification. Here we describe a specific chemoenzymatic approach to 5-hmC detection in DNA samples by using new uridine 5′-diphosphoglucosamine (UDP-GlcN) probes. Our approach requires modification of the glucose moiety of UDP-Glc with small amino groups and transfer of these glucose derivatives to the hydroxy moiety of 5-hmC by using T4 phage glucosyltransferases. We evaluated the transfer efficiencies of three glucosyltransferases (wild-type α- and β-GTs and a Y261L mutant β-GT) with five different UDP-Glc derivatives containing functionalized groups for subsequent bioconjugation and detection. Our results indicate that UDP-6-N3-Glc, UDP-6-GlcN, and UDP-2-GlcN can be transferred by β-GT with efficiencies similar to that seen with the native UDP-Glc cofactor. 6-N3-Glc- and 6-GlcN-containing oligonucleotides were selectively labeled with reactive fluorescent probes. In addition, a 2 kb DNA fragment modified with 2-GlcN groups was specifically detected by use of a commercially available antiglucosamine antibody. Alternative substrates for β-GT and correlated glycosyltransferases might prove useful for the study of the function and dynamics of 5-hmC and other modified nucleotides, as well as for multiplex analysis.