Small G D, Greimann C S
Nucleic Acids Res. 1977 Aug;4(8):2893-902. doi: 10.1093/nar/4.8.2893.
A UV-specific endonuclease was used to detect ultraviolet light-induced pyrimidine dimers in chloroplast DNA of Chlamydomonas reinhardi that was specifically labeled with tritiated thymidine. All of the dimers induced by 100 J/m2 of 254 nm light are removed by photoreaction. Wild-type cells exposed to 50 J/m2 of UF light removed over 80% of the dimers from chloroplast DNA after 24 h of incubation in growth medium in the dark. A UV- sensitive mutant, UVS1, defective in the excision of pyrimidine dimers from nuclear DNA is capable of removing pyrimidine dimers from chloroplast DNA nearly as well as wild-type, suggesting that nuclear and chloroplast DNA dark-repair systems are under separate genetic control.
使用一种紫外线特异性核酸内切酶来检测莱茵衣藻叶绿体DNA中紫外线诱导的嘧啶二聚体，该叶绿体DNA用氚标记的胸腺嘧啶进行了特异性标记。100 J/m²的254 nm光诱导产生的所有二聚体都可通过光反应去除。暴露于50 J/m²紫外线的野生型细胞在黑暗中于生长培养基中培养24小时后，叶绿体DNA中超过80%的二聚体被去除。一个对紫外线敏感的突变体UVS1，其从核DNA中切除嘧啶二聚体存在缺陷，但它从叶绿体DNA中去除嘧啶二聚体的能力几乎与野生型相同，这表明核DNA和叶绿体DNA的暗修复系统受不同的遗传控制。
