Effects of anti-sense oligonucleotides directed toward dihydrofolate reductase RNA in mammalian cultured cells

Multiple Forms of Dihydrofolate Reductase from Cultured Mammalian Cells

Purification and properties of dihydrofolate reductase from cultured mammalian cells.

Dihydrofolate reductase was purified quickly and simply from small quantities of cultured mammalian cells by affinity chromatography. On gel electrophoresis of the purified enzyme, multiple bands of activity resulted from enzyme-buffer interaction at low but not high buffer concentration. A Ferguson plot (Ferguson, 1964) showed that this heterogeneity was due to a charge difference with no alte...

Effects of 5-fluorouracil on dihydrofolate reductase and dihydrofolate reductase mRNA from methotrexate-resistant KB cells.

Growth of methotrexate-resistant dihydrofolate reductase gene-amplified KB cells in the presence of 5-fluorouracil results in an increase in dihydrofolate reductase mRNA. This increase can be solely attributed to a species of RNA of approximately 3.5 kilobase pairs in size. Although dihydrofolate reductase enzyme activity increases per cell with increasing 5-fluorouracil, there is a decrease of...

Elevation of dihydrofolate reductase, thymidylate synthetase, and thymidine kinase in cultured mammalian cells after exposure to folate antagonists.

Roswell Park Memorial Institute 4265 human lymphoblasts were grown with three dihydrofolate reductase inhibitors: a 2,4-diaminopteridine, methotrexate; a 2,4-diaminoquinazoline, chlorasquin; and, a 2,4-diaminotriazine, triazinate. In the absence of inhibitor, dihydrofolate reductase activity increased to a peak at mid-log growth and then declined during the later growth stages. When cells were ...

Specific Inhibition of the Expression of the Promyelocytic Leukemia (PML) Protein by Anti-Sense Oligonucleotides

In the present study, using anti-sense oligonucleotides the inhibition of expression of the PML protein hasbeen investigated. The anti-sense oligonucleotides were designed against the translation initiation site ofthe PML gene, and their effects were investigated on cellular growth and DNA synthesis. Incubation of normalhuman fibroblast cells with the anti-sense oligonucleotid...