The Induction of Resistance to Alkylation Damage in Mammalian Cells
We are continuously exposed to non-toxic levels of carcinogens both from our environment and from our diet. It would therefore seem important to determine how cells respond to this particular kind of treatment. Some years ago, an attempt to simulate this chronic environmental exposure to mutagens revealed the existence of an inducible antimutagenic DNA repair pathway in E. coli — the adaptive DNA repair pathway (1). The obvious progression from finding a new type of DNA repair in E. coli was to ask whether an equivalent pathway exists in mammalian cells, and ultimately whether it exists in human cells. We now have good biological evidence for the existence of an adaptive DNA repair pathway in cultured rodent and human cell lines (2). In order to set the scene for our recent findings in mammalian cells, we should first consider what is presently known about E. coli adaptation.
KeywordsAdaptive Response Sister Chromatid Exchange GM637 Cell Methyl Guanine Alkylation Damage
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