title: Oxidized C5-methyl cytosine bases in DNA: 5-Hydroxymethylcytosine; 5-formylcytosine; and 5-carboxycytosine.
abstract: Recent reports suggest that the Tet enzyme family catalytically oxidize 5-methylcytosine in mammalian cells. The oxidation of 5-methylcytosine can result in three chemically distinct species - 5-hydroxymethylcytsine, 5-formylcytosine, and 5-carboxycytosine. While the base excision repair machinery processes 5-formylcytosine and 5-carboxycytosine rapidly, 5-hydroxymethylcytosine is stable under physiological conditions. As a stable modification 5-hydroxymethylcytosine has a broad range of functions, from stem cell pluriopotency to tumorigenesis. The subsequent oxidation products, 5-formylcytosine and 5-carboxycytosine, are suggested to be involved in an active DNA demethylation pathway. This review provides an overview of the biochemistry and biology of 5-methylcytosine oxidation products.
authors.affiliation: Institute of Medical Microbiology, Oslo University Hospital, Rikshospitalet, Norway; Institute of Basic Medical Sciences, University of Oslo, PO Box 1018 Blindern, N-0315 Oslo, Norway.
authors.forename: Arne
authors.initials: A
authors.lastname: Klungland
authors.affiliation: Institute of Medical Microbiology, Oslo University Hospital, Rikshospitalet, Norway. Electronic address: Adam.robertson@rr-research.no.
authors.forename: Adam B
authors.initials: AB
authors.lastname: Robertson
mesh_terms: D044503:5-Methylcytosine / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D063646:Carcinogenesis; D000066673:Cell Self Renewal; D003596:Cytosine / Q000031:analogs & derivatives / Q000737:chemistry; D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D019175:DNA Methylation; D004260:DNA Repair; D006801:Humans; D010084:Oxidation-Reduction; D014158:Transcription, Genetic
chemical_list: C560973:5-formylcytosine; C011865:5-hydroxymethylcytosine; D044503:5-Methylcytosine; C000618843:5-carboxycytosine; D003596:Cytosine; D004247:DNA
keywords: 5-carboxycytosine; 5-formylcytosine; 5-hydroxymethylcytosine; 5-methylcytosine; DNA demethylation; Epigenetics