Zhang Liangliang, Liang Duanwei, Wang Yuan, Li Dong, Zhang Jinhao, Wu Li, Feng Mengke, Yi Fan, Xu Luzheng, Lei Liandi, Du Quan, Tang XinJing
State Key Laboratory of Natural and Biomimetic Drugs , School of Pharmaceutical Sciences , Peking University , No. 38, Xueyuan Rd , Beijing 100191 , China . Email:
Medical and Health Analytical Center , Peking University , No. 38, Xueyuan Rd , Beijing 100191 , China.
Chem Sci. 2017 Oct 19;9(1):44-51. doi: 10.1039/c7sc03842a. eCollection 2018 Jan 7.
By means of RNA interference (RNAi), small interfering RNAs (siRNAs) play important roles in gene function study and drug development. Recently, photolabile siRNAs were developed to elucidate the process of gene silencing in terms of space, time and degree through chemical modification of siRNAs. We report herein a novel type of photolabile siRNA that was synthesized through cyclizing two ends of a single stranded RNA with a photocleavable linker. These circular siRNAs became more resistant to serum degradation. Using reporter assays of firefly/ luciferase and GFP/RFP, the gene silencing activities of caged circular siRNAs for both genes were evaluated in HEK293 cells. The results indicated that the target genes were successfully photomodulated using these caged circular siRNAs that were formed by caged circular antisense guide RNAs and their linear complementary sense RNAs. Using the caged circular siRNA targeting GFP, we also successfully achieved photomodulation of GFP expression in mice. Upon further optimization, this new type of caged circular siRNA is expected to be a promising tool for studying gene therapy.
通过RNA干扰（RNAi），小干扰RNA（siRNA）在基因功能研究和药物开发中发挥着重要作用。最近，通过对siRNA进行化学修饰，开发出了光不稳定siRNA，以从空间、时间和程度方面阐明基因沉默的过程。我们在此报告一种新型的光不稳定siRNA，它是通过用可光裂解的连接子将单链RNA的两端环化而合成的。这些环状siRNA对血清降解更具抗性。使用萤火虫荧光素酶/荧光素酶和绿色荧光蛋白/红色荧光蛋白的报告基因检测，在HEK293细胞中评估了笼形环状siRNA对这两个基因的基因沉默活性。结果表明，使用由笼形环状反义引导RNA及其线性互补正义RNA形成的这些笼形环状siRNA成功地对靶基因进行了光调制。使用靶向绿色荧光蛋白的笼形环状siRNA，我们还成功地在小鼠中实现了绿色荧光蛋白表达的光调制。经过进一步优化，这种新型的笼形环状siRNA有望成为研究基因治疗的有前途的工具。
