DsRed-expressing cells before (upper) and after (lower) “greening” of the cytoplasm (left) or nucleus (right).
Parker/Macmillan
First there was green fluorescent protein (GFP) from jellyfish, then came red fluorescent protein (DsRed) from coral. Now researchers from the University of California at Irvine show that DsRed may become equally indispensable for tracking cells, organelles, and fusion proteins by turning them… green?
Selective labeling of mitochondrial subpopulations using PARTCELL.
Whitesides/Macmillan
Ian Parker says he and his colleagues made the discovery quite by accident while exploring the use of DsRed for multiphoton confocal imaging. Brief exposure to a femtosecond-pulsed laser beam turned DsRed's fluorescence from red to green when viewed with a conventional one-photon microscope. The excitation, they explain, selectively bleaches the mature, red-emitting form of DsRed, which enhances emission from the immature green form.
The color change persists for hours or even days, and appears to do...
