Estradiol receptor potentiates, in vitro, the activity of 5-methylcytosine DNA glycosylase.
At a concentration of 5 x 10(-9) M of hemi-methylated DNA (one order of magnitude below the K(m)), MCF-7 (a human breast carcinoma cell line) nuclear extracts potentiate the activity of 5-methylcytosine DNA glycosylase (5-MCDG, alias G/T mismatch DNA glycosylase). Depending on the ratio between MCF-7 nuclear extracts and 5-MCDG, there is an up to 10-fold increase in 5-MCDG activity. The potentiation of 5-MCDG by MCF-7 nuclear extracts requires an estradiol response element adjacent to the hemi-methylated site. Depletion of the estradiol receptor from MCF-7 nuclear extracts with specific antibodies abolishes the potentiation of 5-MCDG activity. The estradiol receptor present in MCF-7 nuclear extracts can be precipitated with antibodies directed against 5-MCDG. Reciprocally, antibodies directed against the estradiol receptor precipitate 5-MCDG. The results indicate the formation of a complex between the estradiol receptor and 5-MCDG.
Jost
Jean-Pierre
JP
Friedrich Miescher Institute, Maulbeerstrasse 66, CH-4058, Basel, Switzerland. jost@fmi.ch
Thiry
Stéphane
S
Siegmann
Michel
M
D001483:Base Sequence; D001943:Breast Neoplasms / Q000378:metabolism; D002457:Cell Extracts; D002467:Cell Nucleus / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D045647:DNA Glycosylases; D005260:Female; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D009699:N-Glycosyl Hydrolases / Q000378:metabolism*; D011233:Precipitin Tests; D011959:Receptors, Estradiol / Q000276:immunology / Q000378:metabolism*; D020218:Response Elements; D014407:Tumor Cells, Cultured
D002457:Cell Extracts; D011959:Receptors, Estradiol; D004247:DNA; C093335:5-methylcytosine-DNA glycosylase; D045647:DNA Glycosylases; D009699:N-Glycosyl Hydrolases