[On the impossibility of the incorporation of 5-methylcytosine and its nucleosides into higher plant DNA].
No radioactivity was detected in 5-methylcytosine isolated from wheat DNA after incubation of wheat seedlings with 3H-labelled 5-methylcytosine, 5-methylcytidine and 5-methyldeoxycytidine. No label from 3H-5-methylcytosine was found in DNA of seedlings. After incubation of seedlings with 3H-labelled nucleosides of 5-methylcytosine, radioactivity was discovered only in thymine of DNA. Thus 5-methylcytosine and its nucleosides can not be used in plants as direct precursors of 5-methyl cytosine residues in DNA, but nucleosides of 5-methylcytosine may be deaminated to thymidine (or deoxythymidine) and subsequently incorporated into DNA.
D003562:Cytidine / Q000031:analogs & derivatives* / Q000378:metabolism; D003596:Cytosine / Q000031:analogs & derivatives* / Q000378:metabolism; D004247:DNA / Q000378:metabolism*; D003841:Deoxycytidine / Q000031:analogs & derivatives / Q000378:metabolism; D010944:Plants / Q000378:metabolism*; D013942:Thymine Nucleotides / Q000378:metabolism; D014908:Triticum
D013942:Thymine Nucleotides; D003841:Deoxycytidine; D003562:Cytidine; D003596:Cytosine; D004247:DNA; C016569:5-methyldeoxycytidine; C016568:5-methylcytidine
O nevozmozhnosti vkliucheniia 5-metiltsitozina i ego nukleozidov v DNK vysshikh rastenií.