Quantitative analysis of the flexibility effect of cisplatin on circular DNA.
We study the effects of cisplatin on the circular configuration of DNA using atomic force microscopy (AFM) and observe that the DNA gradually transforms to a complex configuration with an intersection and interwound structures from a circlelike structure. An algorithm is developed to extract the configuration profiles of circular DNA from AFM images and the radius of gyration is used to describe the flexibility of circular DNA. The quantitative analysis of the circular DNA demonstrates that the radius of gyration gradually decreases and two processes on the change of flexibility of circular DNA are found as the cisplatin concentration increases. Furthermore, a model is proposed and discussed to explain the mechanism for understanding the complicated interaction between DNA and cisplatin.
Key Laboratory of Soft Matter Physics, Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.
Chao
C
Ji
Lingyun
L
Zhang
Peng-Ye
PY
Wang
D000970:Antineoplastic Agents / Q000494:pharmacology*; D002945:Cisplatin / Q000494:pharmacology*; D004270:DNA, Circular / Q000737:chemistry* / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D009690:Nucleic Acid Conformation / Q000187:drug effects*; D018583:Pliability / Q000187:drug effects
D000970:Antineoplastic Agents; D004270:DNA, Circular; D002945:Cisplatin