Identification and characterization of a mutation in the dihydrofolate reductase gene from the methotrexate-resistant Chinese hamster ovary cell line Pro-3 MtxRIII.

@article{Dicker1990IdentificationAC,
  title={Identification and characterization of a mutation in the dihydrofolate reductase gene from the methotrexate-resistant Chinese hamster ovary cell line Pro-3 MtxRIII.},
  author={A. Dicker and M. Volkenandt and B. Schweitzer and D. Banerjee and J. Bertino},
  journal={The Journal of biological chemistry},
  year={1990},
  volume={265 14},
  pages={
          8317-21
        }
}
A methotrexate-resistant Chinese hamster ovary cell line (Pro-3 MtxRIII), resistant due to a low-level amplified, altered target enzyme, dihydrofolate reductase (DHFR), has been characterized on the molecular level. The cDNA and coding regions of all six DHFR exons were amplified in vitro using Taq polymerase and directly sequenced. Analysis of the Pro-3 MtxRIII DHFR cDNA demonstrated a C----T base transition at nucleotide 67 that results in the substitution of phenylalanine for leucine at… Expand
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