Repression of transient expression by DNA methylation in transcribed regions of reporter genes introduced into cultured human cells.
We developed a convenient method to methylate all CpG dinucleotides in both strands in a selected region of a plasmid, and investigated the effect of DNA methylation in the transcribed regions of reporter genes on the transient expression in HeLa cells. In a construct containing the chloramphenicol acetyltransferase (CAT) gene linked to the SV40 early promoter, methylation in the CAT structural gene repressed CAT activity. Methylation in the transcribed region of the Escherichia coli lacZ gene driven by the human cytomegalovirus immediate early promoter also inhibited expression of beta-galactosidase activity. These results suggest that methylation in the transcribed region as well as promoter methylation may affect transcription.
Komura
J
J
Department of Radiation Research, Tohoku University School of Medicine, Sendai, Japan.
Okada
T
T
Ono
T
T
D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D003587:Cytomegalovirus / Q000235:genetics; D004247:DNA / Q000378:metabolism*; D017781:Genes, Immediate-Early; D017930:Genes, Reporter; D006367:HeLa Cells; D006801:Humans; D008745:Methylation; D011401:Promoter Regions, Genetic; D013539:Simian virus 40 / Q000235:genetics; D014158:Transcription, Genetic; D014162:Transfection; D001616:beta-Galactosidase / Q000235:genetics
D004247:DNA; D015500:Chloramphenicol O-Acetyltransferase; D001616:beta-Galactosidase