Promega Corp. announced that it has signed an agreement with Leica Microsystems to enable fluorescent imaging of proteins in live cells. Under the terms of the agreement, Promega will develop fluorescent ligands for its HaloTag fusion proteins, that will be used to label proteins within live cells so that they can be visualized with Leica's TCS STED (stimulated emission depletion) superresolution microscope. Developed in the laboratory of Dr. Stefan Hell of the Max-Planck Institute in Germany, STED microscopy enables the investigation of structural details below the 100nm range.
Commonly used fluorescent proteins such as GFP are not optimal for use with high-powered STED technology as they are prone to photobleaching and lack appropriate spectral properties. In addition, alternative methods of labeling proteins with fluorescent antibodies are only applicable for fixed cells. Therefore, the agreement between Promega and Leica Microsystems will enable imaging of proteins within live cells at sub 100nm range.
Promega has been working with Leica Microsystems since 2006 to develop novel ways to label proteins within cells using its proprietary HaloTag® technology.