Organelle membrane-specific chemical labeling and dynamic imaging in living cells

Abstract

Lipids play crucial roles as the structural elements, signalling molecules, and material transporters in cells. However, the functions and dynamics of lipids within cells remain unclear because of a lack of methods to selectively label lipids in specific organelles and trace their movement by live-cell imaging. We describe here a technology for the selective labelling and fluorescence micro/nanoscopic imaging of phosphatidylcholines in target organelles. The approach involves the metabolic incorporation of azido-choline followed by a spatially limited bioorthogonal reaction, which enables the visualization and quantitative analysis of interorganelle lipid transport in live cells. Most importantly, with live-cell imaging, we obtained direct evidence that the autophagosome membrane originates from the endoplasmic reticulum. This method is simple and robust, and thus powerful for real-time tracing of interorganelle lipid trafficking.

A Nature‐Inspired Metal–Organic Framework Discriminator for Differential Diagnosis of Cancer Cell Subtypes

“…Bioorthogonal chemistry has gained great prominence in tagging biomolecules in their native environment for probing and manipulating physiological processes. [1][2][3] In the labeling reactions,am etabolic precursor with bioorthogonal group is first incorporated into target biomolecules via the underlying biosynthetic machinery,f ollowed by conjugation with an exogenous complementary reporter for detection. [4,5] Cooperated with bioorthogonal chemistry,metabolic glycan labeling holds tremendous promise for cell surface engineering, tumor targeted therapy,i mmunomodulation, glycan imaging and glycoproteomic profiling.…”

Time-resolved analysis of photoluminescence at a single wavelength for ratiometric and multiplex biosensing and bioimaging

“…Photoluminescence bioimaging tracks emissive probes in biological environments to create visual images by analyzing and processing luminescence signals, giving structural and functional information of biological molecules, [1][2][3][4][5][6][7] organelles, [8][9][10][11] living cells, [12][13][14][15][16] tissues, [17][18][19][20] and organs. 21,22 Laser scanning confocal microscopy has been widely used for analyzing luminescence intensity of a probe to construct images, which simply and directly reect the spatial distribution and local concentration of the probe at the subcellular level.…”

Organelle‐Selective Labeling of Choline‐Containing Phospholipids (CPLs) and Real‐Time Imaging in Living Cells

“…Prolonged culture or perturbed culture conditions such as drug treatment, serum depletion, or heat stimulation can promote intracellular translocation of OCR‐labeled CPLs. On the basis of our results, rhodol‐labeled CPLs are gradually translocated from ER‐Golgi to other cellular membranes such as mitochondria, lysosomes, the plasma membrane, and autophagosomes, while rhodamine‐labeled CPLs predominantly reside in mitochondria, partially moving to lysosomes (Tamura et al., 2020). This method is compatible with multi‐color co‐localization analysis, by which the localization of labeled CPLs can be compared with those of protein‐ or compound‐based organelle markers visualized by transfection reagents or chemical organelle‐targeting dyes.…”