Department of Cancer Biology, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA.
School of Pharmaceutical Sciences, Shandong University, Jinan, 250101, China.
Small. 2018 Oct;14(41):e1802166. doi: 10.1002/smll.201802166. Epub 2018 Sep 14.
Combining luminescent transition metal complex with super-resolution microscopy is an excellent strategy for the long-term visualization of the dynamics of subcellular structures in living cells. However, it remains unclear whether iridium(III) complexes are applicable for a particular type of super-resolution technique, structured illumination microscopy (SIM), to image subcellular structures. Herein, an iridium(III) dye, to track mitochondrial dynamics in living cells under SIM is described. The dye demonstrates excellent specificity and photostability and satisfactory cell permeability. While using SIM to image mitochondria, an ≈80 nm resolution is achieved that allows the clear observation of the structure of mitochondrial cristae. The dye is used to monitor and quantify mitochondrial dynamics relative to lysosomes, including fusion involved in mitophagy, and newly discovered mitochondria-lysosome contact (MLC) under different conditions. The MLC remains intact and fusion vanishes when five receptors, p62, NDP52, OPTN, NBR1, and TAX1BP1, are knocked out, suggesting that these two processes are independent.
将发光过渡金属配合物与超分辨率显微镜相结合，是长期可视化活细胞亚细胞结构动态的绝佳策略。然而，铱(III)配合物是否适用于特定类型的超分辨率技术——结构光照明显微镜(SIM)，以对亚细胞结构进行成像，目前仍不清楚。在此，描述了一种用于在 SIM 下跟踪活细胞中线粒体动力学的铱(III)染料。该染料表现出优异的特异性、光稳定性和令人满意的细胞通透性。在使用 SIM 对线粒体进行成像时，可实现约 80nm 的分辨率，从而能够清晰观察线粒体嵴的结构。该染料可用于监测和量化线粒体与溶酶体的动力学关系，包括涉及自噬的融合，以及在不同条件下新发现的线粒体-溶酶体接触(MLC)。当敲除五个受体(p62、NDP52、OPTN、NBR1 和 TAX1BP1)时，MLC 保持完整，融合消失，这表明这两个过程是独立的。
