The mechanism of inhibition of protein synthesis by 5-azacytidine in HeLa cells

Abstract

The base analogue 5-azacytidine is shown to inhibit protein synthesis in HeLa cells with a half-life of 90 min. Inhibition apparently occurs at the level of initiation of translation. The analogue must be incorporated into RNA, since its effect is suppressed by actinomycin. The defective RNA which causes inhibition is probably neither messenger nor ribosomal RNA. 5-Azacytidine may interfere with the actinomycin-sensitive metabolism involved in initiating translation in HeLa cells.