NEW YORK, April 22 - Researchers at the University of California, San Diego have used a genetic tagging technique to monitor protein dynamics in living cells and permit both light and electron microscope imaging of protein activity.
The USCD team, comprising scientists from the School of Medicine and National Center for Microscopy and Imaging Research, developed this labeling technique in order to pair dynamic fluorescent images from living cells with high-resolution images from electron microscopy.
They created the tag by fusing a tetracysteine receptor domain into a common connexin protein. This domain binds with red and green fluorescin derivatives so that the stain permitted the team to monitor protein transport in active cells. Other properties of one tag/dye complex were used to create a stable stain that also made the recombinant protein visible under high-resolution electron microscopy.
The team, whose research is published in the April 19 issue of Science, used this technique to monitor gap junctions in which connexin proteins create dynamically modeled tissue membranes. But they hope the technique could be used to monitor any protein as it is transported and incorporated into other structures.
Now that the human genome project is complete, said study author and UCSD professor of neurosciences Mark Ellisman in a statement, the next challenge is to develop technologies and methodologies to mark and observe proteins in living cells. "The technology we have developed delivers important new capabilities at these next levels of scientific research," he said.