%0 Journal Article
%T Carboxylation of cytosine (5caC) in the CG dinucleotide in the E-box motif (CGCAG|GTG) increases binding of the Tcf3|Ascl1 helix-loop-helix heterodimer 10-fold.
%A Golla JP
%A Zhao J
%A Mann IK
%A Sayeed SK
%A Mandal A
%A Rose RB
%A Vinson C
%J Biochem Biophys Res Commun
%V 449
%N 2
%D Jun 2014 27
%M 24835951
%F 3.322
%R 10.1016/j.bbrc.2014.05.018
%X Three oxidative products of 5-methylcytosine (5mC) occur in mammalian genomes. We evaluated if these cytosine modifications in a CG dinucleotide altered DNA binding of four B-HLH homodimers and three heterodimers to the E-Box motif CGCAG|GTG. We examined 25 DNA probes containing all combinations of cytosine in a CG dinucleotide and none changed binding except for carboxylation of cytosine (5caC) in the strand CGCAG|GTG. 5caC enhanced binding of all examined B-HLH homodimers and heterodimers, particularly the Tcf3|Ascl1 heterodimer which increased binding ~10-fold. These results highlight a potential function of the oxidative products of 5mC, changing the DNA binding of sequence-specific transcription factors.