Living Cells and Dynamic Molecules Observed with the Polarized Light Microscope: the Legacy of Shinya Inoué

Abstract

In 1948, Shinya Inoué arrived in the United States for graduate studies at Princeton. A year later he came to Woods Hole, starting a long tradition of summer research at MBL, which quickly became Inoué’s scientific home. Primed by his Japanese mentor Katsuma Dan, Inoué followed Dan’s mantra to work with healthy living cells, on a fundamental problem (mitosis), with a unique tool set that he refined for precise and quantitative observations (polarized light microscopy), and a fresh and brilliant mind that was unafraid of challenging current dogma. Building on this potent combination, Inoué contributed landmark observations and concepts in cell biology, including the notion of dynamic fine structures inside living cells in which molecular assemblies such as mitotic spindle fibers exist in a delicate equilibrium with their molecular building blocks suspended in the cytoplasm. In the late 1970s and 80s, Inoué and others at the MBL were instrumental in conceiving of video microscopy, a groundbreaking technique that married light microscopy and electronic imaging and ushered in a revolution in how we know and what we know about living cells and the molecular mechanisms of life. This article recounts some of Inoué’s accomplishments and how his legacy has shaped current activities in polarized light imaging at the MBL.

Synthesis, Mesomorphism and the Optical Properties of Alkyl-deuterated Nematogenic 4-[(2,6-Difluorophenyl)ethynyl]biphenyls

“…Liquid crystal devices can control the wavelength, polarization and phase, so they can be used to improve the performance of optical imaging systems even for biomedical applications, e.g., LC polarization controllers for bio-imaging, where LCs act as a simple variable retarder creating and controlling polarization changes [ 35 , 36 , 37 , 38 ]. LC-tunable filters were successfully demonstrated in research labs and some industrial environments to have a great potential in agriculture, process inspection, remote sensing and medical diagnosis for spectral and polarization imaging (SPI) and hyperspectral imaging (HSI).…”

Birefringence Changes of Dendrites in Mouse Hippocampal Slices Revealed with Polarizing Microscopy

“…Polarized light microscopy has been a powerful tool to investigate the anisotropic structural signatures of molecular assemblies and their dynamics in living cells in a label-free and noninvasive manner (21). The biological polarized light microscope was developed more than half a century ago to observe the assembly and disassembly of protein polymers that produce mechanical forces for segregating chromosomes in the process of cell division (22,23).…”

Instantaneous polarized light imaging reveals activity dependent structural changes of dendrites in mouse hippocampal slices

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