EFFECT OF RABBIT RETICULOCYTES 5srRNA ON DNA SYNTHESIS OF MOUSE MYELOMA CELLS SP2/0 / 解剖学报

5srRNA was isolated and purified from the reticulocytes of rabbit. It labeled with ~(125)I, then incubated with mouse myeloma cells (SP2/0). By autoradiography it was observed that ~(125)I-SsrRNA could pass into the nuclei of the cells. In a separate experiment, it showed that the incorporation rate of ~3H-TdR into nuclei of SP2/0 after incubation with 5srRNA was decreased as compared with that f control group, hence the result indicates that 5srRNA inhibits DNA synthesis of the SP2/0 cells and it seems to play a role in the regulation of gene expression through its hybridization with DNA sequences of the SP2/0 cells. Thus it is likely that 5srRNA might act as "erythroid denucleation factor".