'Exotic' virus replication mechanism discovered

11 Dec 2014

Polymerase Sliding Mechanism for NNS RNA Virus Replication
Source: Dave Meikle, University of Utah.
This illustration depicts an exotic mechanism by which a family of viruses named NNS RNA viruses may replicate to make copies of themselves, according to a University of Utah study. The family includes a livestock virus named VSV as well as viruses responsible for Ebola, measles, rabies and a common respiratory virus, RSV. The mechanism may serve as a target for new drugs against Ebola in five to 10 years. The yellowish strand is a viral genetic blueprint made of RNA and covered by bead-like proteins. The orange, ball-shaped objects are enzymes called polymerases, which normally read and copy the RNA to make new virus particles. That process can begin only when some polymerases attach to the correct end of the RNA and start reading it, which the two polymerases on the left are doing. The other polymerases (the four on the right side) are attached to the protein-covered RNA but slide along it until they collide with the polymerases that already are reading the RNA. Those collisions kick sliding polymerases loose (top center) so they can float to the proper end of the RNA and start reading it. Researchers hope future drugs can be developed to target this sliding mechanism as a new treatment for Ebola.