Super-resolution imaging of fluorescent dipoles via polarized structured illumination microscopy

• Published in: Nature communications 2019-10, Vol.10 (1), p.4694-10, Article 4694
• Main Authors: Zhanghao, Karl, Chen, Xingye, Liu, Wenhui, Li, Meiqi, Liu, Yiqiong, Wang, Yiming, Luo, Sha, Wang, Xiao, Shan, Chunyan, Xie, Hao, Gao, Juntao, Chen, Xiaowei, Jin, Dayong, Li, Xiangdong, Zhang, Yan, Dai, Qionghai, Xi, Peng
• Format: Article
• Language: English
• Subjects: 14/34; 14/35; 14/63; 631/1647/328/2238; 639/624/1107/328/1652; 639/624/1107/328/2238; Actin; Actins - ultrastructure; Animals; Bacteriophage lambda - genetics; Cell Line, Tumor; Cytoskeleton; Cytoskeleton - ultrastructure; Deoxyribonucleic acid; Dipoles; DNA; DNA - ultrastructure; Dynamic structural analysis; Dynamics; Fluorescence; Fluorescence polarization; Green fluorescent protein; Hippocampus; Hippocampus - cytology; Humanities and Social Sciences; Humans; Hyperspaces; Illumination; Image resolution; Kidney; Mice; Microscopy; Microscopy, Fluorescence - methods; Microscopy, Polarization - methods; Microtubules; multidisciplinary; Myosin; Myosins - ultrastructure; Neurons - ultrastructure; Ring structures; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-019-12681-w

Fluorescence polarization microscopy images both the intensity and orientation of fluorescent dipoles and plays a vital role in studying molecular structures and dynamics of bio-complexes. However, current techniques remain difficult to resolve the dipole assemblies on subcellular structures and their dynamics in living cells at super-resolution level. Here we report polarized structured illumination microscopy (pSIM), which achieves super-resolution imaging of dipoles by interpreting the dipoles in spatio-angular hyperspace. We demonstrate the application of pSIM on a series of biological filamentous systems, such as cytoskeleton networks and λ-DNA, and report the dynamics of short actin sliding across a myosin-coated surface. Further, pSIM reveals the side-by-side organization of the actin ring structures in the membrane-associated periodic skeleton of hippocampal neurons and images the dipole dynamics of green fluorescent protein-labeled microtubules in live U2OS cells. pSIM applies directly to a large variety of commercial and home-built SIM systems with various imaging modality. Polarization microscopy has been combined with single-molecule localization, but it’s often limited in either speed or resolution. Here the authors present polarized Structured Illumination Microscopy (pSIM), a method that uses polarized laser excitation to measure dye orientation during fast super-resolution live cell imaging.