Multiple drug resistance (MDR) mechanisms are known to limit the effectiveness of some cancer chemotherapies, probably through enhancing P-glycoprotein-mediated drug efflux from mammalian cells. Similar mechanisms appear to act in other organisms, including bacteria, and may affect not only the
Retroviral integration mutagenesis and treatment with the frameshift mutagen ICR191 were used to transform v-H-ras expressing PB-3c cells to interleukin-3 (IL-3) independence. Six clones displayed viral integrations into the 3' region of the IL-3 gene thus acting post-transcriptionally by disrupting
T cells undergo rapid clonal expansion upon antigenic stimulation to produce an effective immune response. Any defect in the DNA mismatch repair (MMR) system may have a detrimental effect on T cell proliferation. This study employed an in vitro model
A novel forward mutation assay has been developed in Salmonella typhimurium based on resistance to 5-fluorouracil (FU). The mutational target in the FU assay was determined to be the uracil phosphoribosyl transferase (upp) gene. To validate the upp gene as
As the most nucleophilic site in DNA, the guanine N7 atom is a major site of adduction by a large number of alkylating mutagens and carcinogens. Aflatoxin B1, a powerful mutagen, is believed to act through its reaction with this
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