Download MendeleyA fungal dioxygenase CcTet serves as a eukaryotic 6mA demethylase on duplex DNA.
Mu, Y., Zhang, L., Hu, J., Zhou, J., Lin, H.W., He, C., Chen, H.Z., Zhang, L.(2022) Nat Chem Biol 18: 733-741
- PubMed: 35654845
- DOI: https://doi.org/10.1038/s41589-022-01041-3
- Primary Citation of Related Structures:
7VPN, 7W5P - PubMed Abstract:
N 6 -methyladenosine (6mA) is a DNA modification that has recently been found to play regulatory roles during mammalian early embryo development and mitochondrial transcription. We found that a dioxygenase CcTet from the fungus Coprinopsis cinerea is also a dsDNA 6mA demethylase. It oxidizes 6mA to the intermediate N 6 -hydroxymethyladenosine (6hmA) with robust activity of 6mA-containing duplex DNA (dsDNA) as well as isolated genomics DNA. Structural characterization revealed that CcTet utilizes three flexible loop regions and two key residues-D337 and G331-in the active pocket to preferentially recognize substrates on dsDNA. A CcTet D337F mutant protein retained the catalytic activity on 6mA but lost activity on 5-methylcytosine. Our findings uncovered a 6mA demethylase that works on dsDNA, suggesting potential 6mA demethylation in fungi and elucidating 6mA recognition and the catalytic mechanism of CcTet. The CcTet D337F mutant protein also provides a chemical biology tool for future functional manipulation of DNA 6mA in vivo.
Organizational Affiliation:
Department of Pharmacology and Chemical Biology, State Key Laboratory of Oncogenes and Related Genes, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
