No abstract

This paper compares the repair of DNA single strand breaks (ssb) induced by y-radiation in two strains of Chlamydomonas reinhardtii (137C/+/and UVS-I) and three lines of Pisum sativum (NN 131, 198, 140) differing in the degree of radioresistance. DNA ssb in cells exposed to ~/-rays (50, 100, 200, 500 Gy) were measured by electrophoresis and alkaline unwinding method with subsequent chromatography on hydroxyapatite immediately after irradiation and alter 30 rain of post-irradiation incubation at 25 oC. An increase of double-strand DNA (in %) was found in cells after 30 rain post-irradiation incubation. C. reinhardtii strains displayed an equal level of DNA degradation and repair efficiency in the DNA single strand breaks. The radioresistant line N 198 ofP. saavum is characterized by a lower level of induced DNA ssb and higher efficiency of repair of these breaks as compared with less radioresistant lines NN 131 and 140.

No abstract

No abstract

No abstract