Tsutsui K, Aoyama K, Oda T
Biochem Biophys Res Commun. 1984 Aug 30;123(1):271-7. doi: 10.1016/0006-291x(84)90408-x.
When nascent DNA of SV40 pulse labeled with [alpha-32p]dCTP in a permeable cell system was treated in situ with diisopropylfluorophosphate (DFP), a significant fraction of radioactivity was found to be covalently complexed with proteins. The adduct formation was demonstrated by density separation in CsCl, selective precipitation of the complexed DNA with SDS-KC1, and visualization of cross-linked proteins after SDS-PAGE. No cross-linking occurred with mature SV40 chromatin labeled in vivo and extracted from nuclei of infected cells. The DFP-induced DNA-protein cross-linking reaction appears to involve the protein's sulfhydryl groups since pretreatment with some sulfhydryl reagents completely inhibited the reaction.
当在可渗透细胞系统中用[α-32P]dCTP脉冲标记的SV40新生DNA原位用二异丙基氟磷酸酯（DFP）处理时，发现相当一部分放射性与蛋白质共价结合。通过在CsCl中进行密度分离、用SDS-KCl选择性沉淀复合DNA以及在SDS-PAGE后观察交联蛋白来证明加合物的形成。体内标记并从感染细胞核中提取的成熟SV40染色质未发生交联。DFP诱导的DNA-蛋白质交联反应似乎涉及蛋白质的巯基，因为用一些巯基试剂预处理可完全抑制该反应。
