Liu Chenchen, Yamaguchi Yoshinori, Zhu Xifang, Li Zhenqing, Ni Yi, Dou Xiaoming
Engineering Research Center of Optical Instrument and System, University of Shanghai for Science and Technology, Shanghai, P. R. China.
Institute of Photonics and Biomedicine (IPBM), Graduate School of Science, East China University of Science and Technology (ECUST), Shanghai, P. R. China.
Electrophoresis. 2015 Jul;36(14):1651-7. doi: 10.1002/elps.201500018. Epub 2015 May 15.
The analysis of small interfering RNA (siRNA) is important for gene function studies and drug developments. We employed CE to study the separation of siRNA ladder marker, which were ten double-stranded RNA (dsRNA) fragments ranged from 20 to 1000 bp, in solutions of hydroxyethylcellulose (HEC) polymer with different concentrations and molecular weights (Mws). Migration mechanism of dsRNA during CE was studied by the mobility and resolution length (RL) plots. We found that the RL depended on not only the concentration of HEC, but also the Mw of HEC. For instance, RL of small dsRNA fragment was more influenced by concentration of high Mw HEC than large dsRNA fragment and RL of large dsRNA fragment was more influenced by concentration of low Mw HEC than small dsRNA fragment. In addition, we found electrophoretic evidence that the structure of dsRNA was more compact than dsDNA with the same length. In practice, we succeeded to separate the glyceraldehyde 3-phosphate dehydrogenase siRNA in the mixture of the siRNA ladder marker within 4 min.
对小干扰RNA（siRNA）的分析对于基因功能研究和药物开发至关重要。我们采用毛细管电泳（CE）研究了siRNA阶梯标志物（由10个双链RNA（dsRNA）片段组成，范围从20到1000 bp）在不同浓度和分子量（Mw）的羟乙基纤维素（HEC）聚合物溶液中的分离情况。通过迁移率和分辨率长度（RL）图研究了CE过程中dsRNA的迁移机制。我们发现RL不仅取决于HEC的浓度，还取决于HEC的Mw。例如，小dsRNA片段的RL受高Mw HEC浓度的影响比大dsRNA片段更大，而大dsRNA片段的RL受低Mw HEC浓度的影响比小dsRNA片段更大。此外，我们发现电泳证据表明相同长度的dsRNA结构比dsDNA更紧凑。在实际应用中，我们成功地在4分钟内将甘油醛-3-磷酸脱氢酶siRNA从siRNA阶梯标志物混合物中分离出来。
