Abstract
After irradiation with ultraviolet light, HeLa cells undergo repair replication by which small numbers of bases are inserted into parental strands of DNA molecules. Repair replication is also observed autoradiographically by the incorporation of thymidine or deoxycytidine into DNA during the G1, G2, and mitotic stages of the cell cycle. The effects of a number of compounds, classified into three groups according to their mode of action, on repair replication was determined quantitatively. Compounds that inhibit the synthesis of precursors of DNA inhibit semiconservative replication but do not inhibit repair replication. Compounds that bind to DNA inhibit both semiconservative and repair replication. Iodoacetate and cycloheximide also inhibit both semiconservative and repair replication. From a comparison of the effects of acriflavine and caffeine on repair replication in HeLa cells and on the survival of UV-irradiated mouse L cells, it is concluded that repair replication is probably not the only form of ...
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have