Kotnala Abhay, Gordon Reuven
Department of Electrical Engineering, University of Victoria, Victoria, British Columbia V8W 3P6, Canada.
Biomed Opt Express. 2014 May 21;5(6):1886-94. doi: 10.1364/BOE.5.001886. eCollection 2014 Jun 1.
Here we report on the use of double-nanohole (DNH) optical tweezers as a label-free and free-solution single-molecule probe for protein-DNA interactions. Using this approach, we demonstrate the unzipping of individual 10 base pair DNA-hairpins, and quantify how tumor suppressor p53 protein delays the unzipping. From the Arrhenius behavior, we find the energy barrier to unzipping introduced by p53 to be 2 × 10(-20) J, whereas cys135ser mutant p53 does not show suppression of unzipping, which gives clues to its functional inability to suppress tumor growth. This transformative approach to single molecule analysis allows for ultra-sensitive detection and quantification of protein-DNA interactions to revolutionize the fight against genetic diseases.
在此，我们报告了使用双纳米孔（DNH）光镊作为一种用于蛋白质 - DNA相互作用的无标记、自由溶液单分子探针。通过这种方法，我们展示了单个10碱基对DNA发夹的解链过程，并量化了肿瘤抑制蛋白p53如何延迟解链。从阿伦尼乌斯行为中，我们发现p53引入的解链能垒为2×10^(-20) J，而cys135ser突变型p53并未表现出对解链的抑制作用，这为其无法抑制肿瘤生长的功能提供了线索。这种用于单分子分析的变革性方法能够实现对蛋白质 - DNA相互作用的超灵敏检测和定量，从而彻底改变对抗遗传疾病的斗争。
