The effect of proteinase inhibitors on the level of degradation and unscheduled synthesis of DNA in ultraviolet- and gamma-irradiated cellsof mouse ascitic carcinoma

Proteinase inhibitors (e.g. antipain, pepstatin A, and phenylmethane sulfonyl fluoride) were shown to decrease the rate of incision DNA degradation and the level of unscheduled synthesis of DNA in Ehrlich ascites tumor cells exposed to UV-light and gamma-radiation. The results obtained indicate that nuclear proteinases are involved in regulation of DNA repair process.