Demonstration of the formation of cyclobutane pyrimidine dimers through the excited triplet state mediated by solar UV radiation

我试图证明长波紫外线辐射下环丁烷嘧啶二聚体(CPDS)的形成是通过DNA碱基的激发三重态的光化学反应来调节的。然而，也有人报道，长波紫外线诱导的CPD的形成是由另一种新的机制介导的，这使得我们改变了研究的目标，通过对比研究长波紫外线诱导的突变光谱来表征这种新的机制。我们发现，太阳-紫外线特征突变，我们以前已经确定为太阳紫外线特异的突变，是通过这一新的机制产生的CPD引起的，并且由UVA1诱导最有效。

I tried to demonstrate that the formation of cyclobutane pyrimidine dimers (CPDs) by long wavelength UV radiations is mediated by a photochemical reaction through the excited triplet states of DNA bases. However, it was reported by others that the long wavelength UV-induced CPD formation is mediated by another novel mechanism, which made us change the goal of this research and characterize the novel mechanism by studying comparatively the mutation spectra induced by long wavelength UV. We found that solar-UV signature mutations, which we had identified before as solar UV-specific mutations, are caused through the CPDs produced by this novel mechanism, and are induced most efficiently by UVA1.