Abstract

The effects of the alkylating agents methylene dimethanesulphonate (MDMS), sulphur mustard (SM) and methyl methanesulphonate (MMS) on DNA synthesis have been investigated in Yoshida sarcoma cell lines sensitive (YS) and resistant (YR) to these agents. Measurement of overall DNA synthesis by [ 3H]thymidine uptake into DNA indicated that both MDMS and SM, but not MMS, induced a greater depression of DNA synthesis in YS cells than in YR cells. Analysis of the sizes of newly synthesised strands of DNA by pulse labelling and alkaline sucrose gradient sedimentation revealed that MDMS inhibited the initation of new replicons and also reduced the size of new DNA strands. The relative extents of inhibition of replicon initation in MDMS-treated YS and YR cells were similar and reduced by caffeine while YR cells were comparatively less sensitive to the effect of MDMS on the sizes of DNA molecules synthesised. Similarly, YR cells apparently synthesised longer DNA strands following SM treatment compared to YS cells suggesting an association between the size of DNA molecules synthesized and the sensitivity of Yoshida cells to bifunctional alkylating agents.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.