The difference that linear energy transfer makes to precursors of DNA strand breaks
- Univ. of California, La Jolla, CA (United States)
Using agarose gel electrophoresis, we have measured the yields of DNA single- and double-strand breaks (SSBs and DSBs) for plasmid DNA irradiated in aerobic aqueous solution with either {sup 137}Cs {gamma} rays or {sup 4}He ions with a mean LET of 94 or 150 keV {mu}m{sup {minus}1}. The presence of dimethyl sulfoxide (DMSO) resulted in a decrease in the yields of both SSBs and DSBs, with a greater decrease being apparent for {gamma} irradiation than for {sup 4}He-ion irradiation. Irradiation by {sup 4}He ions in the presence of N-(2-thioethyl)-1,3-diaminopropane (WR-1065) resulted in a decrease in the yield of SSBs and a slightly larger decrease in the yield of DSBs. Together with results obtained previously, these observations suggest a substantial contribution to the formation of SSBs and DSBs by {sup 4}He ions by species containing at leas two radicals and more than two radicals, respectively. 16 refs., 8 figs., 1 tab.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 387381
- Journal Information:
- Radiation Research, Journal Name: Radiation Research Journal Issue: 4 Vol. 145; ISSN 0033-7587; ISSN RAREAE
- Country of Publication:
- United States
- Language:
- English
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