DNA strand breaks and repair synthesis in Yoshida sarcoma: cells with differential sensitivities to bi-functional alkylating agents and UV light.
AffiliationPaterson Laboratories, Christie Hospital and Holt Radium Institute, Manchester M20 9BX (Great Britain)
MetadataShow full item record
AbstractThe induction of DNA-strand breaks and repair synthesis has been examined in cultured Yoshida sarcoma cell lines sensitive (YS) and resistant (YR) to methylene dimethanesulphonate (MDMS). Using an alkaline DNA unwinding-hydroxylapatite technique, we were able to detect breaks in DNA immediately after MDMS treatment and at similar levels in both YS and YR cells. MDMS treatment and post-treatment incubation in the presence of 1-beta-D-arabino-furanosylcytosine (araC) lead to a large increase in the numbers of breaks when compared with MDMS treatment alone which indicated that many of the DNA-strand breaks seen after MDMS treatment were intermediates in excision repair. The magnitude of break incidence with the araC treatment was again equal in YS and YR cells indicating that these 2 lines made enzymic incisions next to MDMS-induced lesions with equal capacities. During incubation following MDMS treatment, the levels of DNA-strand breaks in YR cells were found to decrease more rapidly than in YS cells. Parallel DNA-repair synthesis estimations, using BND-cellulose chromatography, revealed that the increased rate of decline in breaks in YR cells was accompanied by an increase in repair-synthesis activity compared to YS cells. This was interpreted as indicating that an intermediate step in an excision-repair pathway for MDMS-induced lesions was relatively deficient in YS compared to YR cells. A similar difference in the rates of decline of DNA-strand breaks between YS and YR cells was also observed following treatment with UV light to which MDMS-resistant YR cells also display cross-resistance. However, no such difference was detected following treatment with the monofunctional alkylating agent, methyl methanesulphonate, to which YS and YR cells are equally sensitive. These results suggest that resistance to MDMS in the YR cell line is achieved by an increased efficiency in the gap-sealing component of the excision-repair process.
CitationDNA strand breaks and repair synthesis in Yoshida sarcoma: cells with differential sensitivities to bi-functional alkylating agents and UV light. 1981, 83 (2):233-49 Mutat Res
- The effects of bifunctional alkylating agents on DNA synthesis in sensitive and resistant Yoshida cells.
- Authors: Carr FJ, Fox BW
- Issue date: 1982 Aug
- Effect of methyl methanesulphonate (MMS) and methylene dimethanesulphonate (MDMS) on the template activity of DNA isolated from MDMS-sensitive and -resistant Yoshida cells.
- Authors: Institoris E, Fox BW, Fox M
- Issue date: 1975 Dec
- The role of formaldehyde in methylene dimethanesulphonate-induced DNA cross-links and its relevance to cytotoxicity.
- Authors: Bedford P, Fox BW
- Issue date: 1981 Dec
- Comparative studies of DNA cross-linking reactions following methylene dimethanesulphonate and its hydrolytic product, formaldehyde.
- Authors: O'Connor PM, Fox BW
- Issue date: 1987
- Single-strand breaks in DNA during repair of UV-induced damage in normal human and xeroderma pigmentosum cells as determined by alkaline DNA unwinding and hydroxylapatite chromatography: effects of hydroxyurea, 5-fluorodeoxyuridine and 1-beta-D-arabinofuranosylcytosine on the kinetics of repair.
- Authors: Erixon K, Ahnström G
- Issue date: 1979 Feb