Abstract:
:We investigated various parameters associated with the initial selection of mouse 3T6 cells for resistance to single concentrations of methotrexate and characterized resistant colonies for the presence of additional (amplified) copies of the dihydrofolate reductase gene. Our results indicate that the frequency of occurrence of dihydrofolate reductase gene amplification varies with the selecting concentration of methotrexate and is highly variable between clonally derived sublines of mouse 3T6 cells. Second, we increased the frequency of occurrence of cells with amplified dihydrofolate reductase genes by transiently inhibiting DNA synthesis with hydroxyurea before the selection of cells in single concentrations of methotrexate. This effect was dependent on the concentration of hydroxyurea, the time of exposure to the drug, and the time interval between the removal of hydroxyurea and the selection of cells in methotrexate.
journal_name
Mol Cell Bioljournal_title
Molecular and cellular biologyauthors
Brown PC,Tlsty TD,Schimke RTdoi
10.1128/mcb.3.6.1097subject
Has Abstractpub_date
1983-06-01 00:00:00pages
1097-107issue
6eissn
0270-7306issn
1098-5549journal_volume
3pub_type
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pub_type: 杂志文章
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