Stimulated emission depletion (STED) nanoscopy of a fluorescent protein-labeled organelle inside a living cell.

ABSTRACT: We demonstrate far-field optical imaging with subdiffraction resolution of the endoplasmic reticulum (ER) in the interior of a living mammalian cell. The diffraction barrier is overcome by applying stimulated emission depletion (STED) on a yellow fluorescent protein tag. Imaging individual structural elements of the ER revealed a focal plane (x, y) resolution of <50 nm inside the living cell, corresponding to a 4-fold improvement over that of a confocal microscope and a 16-fold reduction in the focal-spot cross-sectional area. A similar gain in resolution is realized with both pulsed- and continuous-wave laser illumination. Images of highly convoluted parts of the ER reveal a similar resolution improvement in 3D optical sectioning by a factor of 3 along the optic axis (z). Time-lapse STED

SUBMITTER: Hein B 

PROVIDER: S-EPMC2538451 | biostudies-literature | 2008 Sep

REPOSITORIES: biostudies-literature