Epigenetic effects of cytosine derivatives are caused by their tautomers in Hoogsteen base pairs
نویسنده
چکیده
Deoxycitidine in solution exists as two tautomers one of which is an “uncanonical” imino one. The latter can dominate with such derivatives as 5methyl, 5-hydroxymethyland 5-formylcytosine. The imino tautomer potentially is able to form a hoosteen GC base pair. To detect such pair, it is suggested to use 1H15N NMR. Formation of GC-Hoogsteen base pair with imino tautomer of cytosine can be a reason for epigenetic effects of 5-methyland , 5hydroxymethylcytosine.
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