信号肽功能化二氧化硅纳米颗粒的线粒体靶向作用研究

Study on the Target Interaction Between Mitochondria and Signal Peptide Functionalized Silica Nanoparticles

以N-(p-Maleimidophenyl)isocyanate(PMPI)为交联剂,将线粒体信号肽分子共价修饰到二氧化硅荧光纳米颗粒表面,构建线粒体信号肽功能化二氧化硅荧光纳米颗粒.采用荧光分光光度计、Zeta电位仪以及透射电子显微镜对修饰前后的二氧化硅纳米颗粒进行了表征.结果表明,信号肽可被成功修饰在纳米颗粒表面,并且纳米颗粒粒径在信号肽分子修饰前后没有发生明显变化.以分离纯化的细胞核作为对照,采用流式细胞术考察了信号肽功能化二氧化硅荧光纳米颗粒与分离纯化后的线粒体的相互作用.结果表明,线粒体信号肽修饰到二氧化硅纳米颗粒表面后依然保持良好的生物活性,能够介导二氧化硅纳米颗粒特异性识别及结合分离纯化的线粒体,从而为线粒体监测及其功能调控研究提供了新的思路.

The mitochondrial signal peptide functionalized fluorescent silica nanoparticles were prepared by conjugated the mitochondrial signal peptide to the nanoparticles through N-（p-maleimidophenyl） isocyanate（PMPI）. The fluorescence spectrophotometer, zeta potential and TEM were used to characterize the fluorescent silica nanoparticles. The results show that the signal peptides are successfully conjugated to the surface of fluorescent silica nanoparticles, and the size of the fluorescent silica nanoparticles do not change obviously before and after modification. With the isolated nucleus as a control, the target interaction between the mitochondrial signal peptides modified fluorescent silica nanoparticles and the isolated mitochondria was investigated by flow cytometry. It was revealed that the bioactivity of the signal peptide was well remained after the conjugation with the silica nanoparticles, and the peptides could facilitate the specific recognition and binding between the silica nanoparticles and the isolated mitochondria, which put forwards a new idea for the monitoring and function controlling of the mitochondria.