The effect of 6-mercaptopurine (6-MP) and its nucleoside and nucleotide derivatives on the rate of RNA synthesis with reticulocyte RNA-dependent RNA polymerase has been examined. Of the 6-MP derivatives tested only 6-mercaptopurine ribo-5′-monophosphate (6-MPR-P) significantly stimulates the rate of RNA synthesis with hemoglobin mRNA as a template while 6-MP and 6-MPR have little or no effect. Kinetic studies have demonstrated that 6-MPR-P activates the RNA-dependent RNA polymerase by increasing the Vmax of the enzyme rather than by decreasing the Km values for the substrates. It is suggested that the stimulation of RNA-dependent RNA synthesis by 6-MPR-P may explain the transient development of megaloblastic anemia following 6-MP therapy.
|Original language||English (US)|
|Number of pages||7|
|Journal||Biochemical and biophysical research communications|
|State||Published - Jan 7 1974|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology