纳米材料对DNA热变性行为的影响

在基因操作过程中经常需要对脱氧核糖核酸（DNA）进行高温处理，如在聚合酶链式反应PCR操作中就需要对模板DNA进行升降温的操作，因此，DNA的热变性行为是关系到一些基因操作效率高低的关键．琼脂糖凝胶电泳实验显示，1972bp的短链入DNA高温处理后在1000bp左右处出现额外一条下带，而且此条带经过37℃处理数小时即可恢复到1972bp，不像48000bp长链）LDNA那样在高温处理后出现弥散现象．另外，显著添加不同的纳米材料对下带出现的温度有明显的影响，意味着添加适量纳米材料可以改变DNA分子结构对温度的敏感性．所发现的下带可能具有尚未报道过的特殊结构．

Influence of Nanomaterials on Heat-Induced Denaturation Process of DNA

In the process of genetic manipulations,DNA is often treated by high temperatures,as in the polymerase chain reaction （PCR）where DNA is subjected to big temperature fluctuations. Therefore the heat-induced denaturation process is closely related with efficiencies of DNA manipulations. When a 1 972 bp short k DNA fragment was treated by agarose gel electrophoresis at high temperature,a lower band with the size of about 1 000 bp repeatedly appeared;Moreover,the lower band can be resumed to 1 972 bp after a few hours incubation at 37℃ ,while the 48 000 bp long k DNA only demonstrated dispersion after the treatment of high temperature. In this study,it is found that different nanomaterials differentially influenced the heat-induced denaturation process of DNA by changing the behavior of the lower band that might possess a specific structure never reported. The results suggest that nanomaterials change the temperature sensitivity of DNA structure.