Abstract— Simian virus 40 chromosomes were used to determine whether packaging of DNA into chromatin affected the yield of cyclobutane pyrimidine dimers introduced by ultraviolet light (254 nm). SV40 chromatin and purified SV40 DNA (radioactively labeled with different isotopes) were mixed and irradiated in vitro. The proteins were extracted and pyrimidine dimers detected as sites sensitive to the UV‐endonuclease encoded by bacteriophage T4. When irradiation was carried out in the presence of at least 0.05 M NaCl the same number of dimers were formed in chromatin as in free DNA. Irradiation in the absence of NaCl, however, reduced the relative yield of dimers in chromatin to 89% of that in free DNA. Different methods of chromatin preparation did not influence these results.
|Original language||English (US)|
|Number of pages||5|
|Journal||Photochemistry and Photobiology|
|State||Published - May 1984|
ASJC Scopus subject areas
- Physical and Theoretical Chemistry