SIRNA NANOPARTICLES

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 由siRNA和脂类氨基糖苷衍生物组成的复合体最近被Cryo-EM成像，显示出典型的层状微结构。 在我们的实验室中，我们使用各种脂类系统制备了脂类siRNA载体，这些体系已经成功地用于基因沉默活动。脂质-siRNA的相行为似乎非常丰富，到目前为止，我们已经通过X射线散射鉴定了三种超分子结构。具体地说：i)用市售的阳离子/非离子脂类获得的片状相，ii)用我们实验室合成的多价阳离子脂类得到的二维六方结构，以及iii)由“立方形成”的中性脂类和“自制”的多价阳离子脂类的组合得到的双连续立方相(以及商用)。此外，我们观察到，阶段的性质对SE有很大的影响。 我们提出了冷冻-EM实验，以获得脂类纳米颗粒单独以及与siRNA聚集后的2D图像。我们的长期目标是在脂质-siRNA聚合体中定位siRNA结构域。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Complexes comprising siRNA and lipidic aminoglycoside derivatives have been recently imaged by Cryo-EM, displaying a typical layered microstructure. In our lab we prepared lipid-siRNA constructs using a variety of lipid systems which have been successfully employed in gene silencing activities. The lipid-siRNA phase behavior appears to be very rich and so far we have identified by X-ray scattering three categories of supramolecular structures. Specifically: i) a lamellar phase obtained with commercially available cationic/non-ionic lipids, ii) a 2D hexagonal structure obtained with multivalent cationic lipids synthesized in our lab, and finally iii) a bicontinuous cubic phase obtained by a combination of a "cubic forming" neutral lipid and "home synthesized" multivalent cationic lipids (as well as commercially available). In addition, we have observed that the nature of the phase has a great impact on SE. We propose Cryo-EM experiments to obtain 2D images of the lipid nanoparticles alone and upon aggregation with siRNA. Our long-term goals are to locate the siRNA domains in the lipid-siRNA aggregate.