A new glow for electron microscopy
The glowing green molecule known as green fluorescent protein (GFP) has revolutionized molecular biology. When GFP is attached to a particular protein inside a cell, scientists can easily identify and locate it using fluorescence microscopy. However, GFP can’t be used with electron microscopy, which offers much higher resolution than fluorescence microscopy. Chemists from MIT have now designed a GFP equivalent for electron microscopy — a tag that allows scientists to label and visualize proteins with unprecedented clarity. “With things that may appear only a few pixels across by fluorescence microscopy — for example, a mitochondrion — you can’t make out any of the internal features. But with electron microscopy it’s very easy to discern the intricate internal structures,” says Jeff Martell, a graduate student in chemistry at MIT and lead author of a paper describing the new tag in the Oct. 21 online edition of Nature Biotechnology.The new tag could...