The DOI matches its Crossref record; 2 of the 2 references it cites were found in a registry or an index.
Selective multiplication of dihydrofolate reductase genes in methotrexate-resistant variants of cultured murine cells.
Open accessAbstract
The rate of dihydrofolate reductase synthesis in the AT-3000 line of methotrexate-resistant murine Sarcoma 180 cells is approximately 200-to 250-fold greater than that of the sensitive, parental line. We have purified cDNA sequences complementary to dihydrofolate reductase mRNA and subsequently used this probe to quantitate dihydrofolate reductase mRNA and gene copies in each of these lines. Analysis of the association kinetics of the purified cDNA with DNA from sensitive and resistant cells indicated that the dihydrofolate reductase gene is selectively multiplied approximately 200-fold in the resistant line. A similar analysis of a partially revertant line of resistant ceils indicated that the loss of resistance observed when the AT-3000 line is grown in the absence of methotrexate is associated with a corresponding decrease in the dihydrofolate reductase gene copy number. In each of these lines the relative number of dihydrofolate reductase gene copies is proportional to the cellular level of dihydrofolate reductase and dihydrofolate reductase mRNA sequences. We have also studied parental and methotrexate-resistant lines of L1210 murine lymphoma cells. Both resistance and an
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Cites
Viral RNA-dependent DNA Polymerase: RNA-dependent DNA Polymerase in Virions of Rous Sarcoma Virus
TEMIN, H. M., & MIZUTANI, S. (1970) · Nature · doi:10.1038/2261211a0 · Cited by 2,128
Viral RNA-dependent DNA Polymerase: RNA-dependent DNA Polymerase in Virions of RNA Tumour Viruses
BALTIMORE, D. (1970) · Nature · doi:10.1038/2261209a0 · Cited by 2,068
Cited by
Croce, C. M. (2008) · New England Journal of Medicine · doi:10.1056/nejmra072367 · Cited by 1,055
Isolation of Chinese hamster cell mutants deficient in dihydrofolate reductase activity
Urlaub, G., & Chasin, L. A. (1980) · Proceedings of the National Academy of Sciences · doi:10.1073/pnas.77.7.4216 · Cited by 876
Antifreeze Proteins of Teleost Fishes
Fletcher, G. L., Hew, C. L., & Davies, P. L. (2001) · Annual Review of Physiology · doi:10.1146/annurev.physiol.63.1.359 · Cited by 508
GENETIC ANALYSIS OF THE MULTIDRUG TRANSPORTER
Gottesman, M. M., Hrycyna, C. A., Schoenlein, P. V., Germann, U. A., & Pastan, I. (1995) · Annual Review of Genetics · doi:10.1146/annurev.ge.29.120195.003135 · Cited by 478
Metadata
- Authors
- Alt, F. W., Kellems, R. E., Bertino, J. R., & Schimke, R. T.
- Venue
- Journal of Biological Chemistry
- Publisher
- Elsevier BV
- Published
- 1978-03
- Volume
- 253
- Issue
- 5
- Pages
- 1357-1370
- ISSN
- 0021-9258 (ISSN-L)
- OpenAlex
- W1507212424
- Cited by
- 941
- References
- 2
- FWCI
- 43.18
- Type
- journal article
- Language
- en
- Open access
- hybrid
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- The paper
- Alt, F. W., Kellems, R. E., Bertino, J. R., & Schimke, R. T. (1978). Selective multiplication of dihydrofolate reductase genes in methotrexate-resistant variants of cultured murine cells. Journal of Biological Chemistry. https://doi.org/10.1016/s0021-9258(17)34875-5
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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).
Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.
