Researchers from University of Warwick developed a ferritin-based microscopy method to view proteins in cells.
Ferritin is a protein produced in mammalian metabolism serving to store iron in the tissues. It maintains the quantity of iron required in the cells. Now researchers from University of Warwick devised a method called FerriTag that enables to view proteins in cells more precisely with an electron microscope (EM). The method enabled the cell to make the tag itself avoiding damage caused by placing it from the outside of the cell. The research led by Dr. Stephen Royle associate professor and Senior Cancer Research UK at Warwick Medical School was published in the journal Nature Communications on July 04, 2018.
The researchers used clathrin-coated pits to precisely localize a protein. These pits are 100 nm wide entry points used by viruses to invade and infect cells. FerriTag enabled the viewing of the exact location of the protein in the pit and on the inside face of the cell’s surface. Previously used methods such as light microscopy showed protein movements. However, the resolution provided was low and could no help locate proteins precisely. The researchers opted electron microscopy that provides a higher resolution, to overcome the hurdle. The proteins were tagged for better observation and correlation with both microscopes. Although tagging offers a wide variety of applications, it has some established drawbacks. Some tagging are not precise enough, or do not function on single proteins. Dr. Royle’s lab created a new tag and fused it with a fluorescent protein to overcome the drawbacks. Furthermore, the hurdle of a mash created when ferritin was fused to a protein was overcome by genetically modifying ferritin so that it could be attached to the protein of interest by using a drug.