Thymine DNA glycosylase specifically recognizes 5-carboxylcytosine-modified DNA
نویسندگان
چکیده
Human thymine DNA glycosylase (hTDG) efficiently excises 5-carboxylcytosine (5caC), a key oxidation product of 5-methylcytosine in genomic DNA, in a recently discovered cytosine demethylation pathway. We present here the crystal structures of the hTDG catalytic domain in complex with duplex DNA containing either 5caC or a fluorinated analog. These structures, together with biochemical and computational analyses, reveal that 5caC is specifically recognized in the active site of hTDG, supporting the role of TDG in mammalian 5-methylcytosine demethylation.
منابع مشابه
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عنوان ژورنال:
دوره 8 شماره
صفحات -
تاریخ انتشار 2012