Properties of DNA-dependent RNA-polymerase from spleens of mice infected with Rauscher leukemic virus
Pravdina, N.F.; Veselovskaia, T.V.; Galegov, G.A.
Biokhimiia 44(6): 1137-1144
1979
ISSN/ISBN: 0320-9725 PMID: 465605 Document Number: 145234
The properties of RNA polymerases A, B and C isolated from the spleens of mice infected with Rauscher leukemia virus were studied. The solubilized RNA polymerases A and B were purified 150- to 300-fold. The dynamic changes in the activities of all forms of RNA polymerases at different stages of leukosis were studied. At the earliest steps of leukosis a 2-fold increase in the RNA polymerase B activity followed by a 5-fold increase in the RNA polymerase A activity was observed. At late stages of leukosis, the activity of RNA polymerase C also increased. The properties of RNA polymerases A and B from the spleens of virus-infected mice were compared to those of the controls. In leukemic tissues the specific activities of RNA polymerases A and B were higher as compared to those of the enzymes isolated from the spleens of non-infected mice. No significant differences in the enzyme properties in normal and virus-infected animals were revealed. Dihydrorifampicin (200 .mu.g/ml) caused a 50% inhibition of RNA polymerase A in vitro but had no effect on the activities of RNA polymerases B and C.