A Comparison of Human O6-Methylguanine-DNA Methyltransferase Promoter Activity in Mer+ and Mer~ Cells1
نویسندگان
چکیده
The activity of the human 06-methylguanine-DNA methyltransferase (MGMT) gene promoter was determined in eight human cell lines by measuring chloramphenicol acetyltransferase activity in a re porter gene system. MGMT promoter activities in cells that do not express MGMT (Mer ) fell within the range of activities seen in cells that do express MGMT (Mer4). The promoter region contains 11 po tential binding sites for the transcription factor Spl, but no correlation was seen between cellular Spl protein and MGMT promoter chloram phenicol acetyltransferase activity. Because Mer cells are not deficient in the factors needed for transcription of MGMT, we suggest that at least two mechanisms regulate MGMT expression. One suppresses MGMT mRNA and protein in Mer cells, and another regulates the levels of constitutive expression in Mer cells. Spl is not a limiting factor in MGMT expression.
منابع مشابه
A comparison of human O6-methylguanine-DNA methyltransferase promoter activity in Mer+ and Mer- cells.
The activity of the human O6-methylguanine-DNA methyltransferase (MGMT) gene promoter was determined in eight human cell lines by measuring chloramphenicol acetyltransferase activity in a reporter gene system. MGMT promoter activities in cells that do not express MGMT (Mer-) fell within the range of activities seen in cells that do express MGMT (Mer+). The promoter region contains 11 potential ...
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