Thwarting cellular enzyme can fight viral infections

(© Image: Depositphotos) - Researchers from FMI have identified a synthetic protein that dampens the activity of a cellular pathway involved in viral infection. The findings could help to develop drugs that combat viruses such as influenza A and Zika. Influenza A virus affects millions of people worldwide and can have serious complications, including bacterial pneumonia, ear infections and the worsening of long-term medical conditions. Once the flu virus enters a cell in the body, it has to release its genetic material, which is packed into a protein shell called capsid. To do so, the virus hijacks some of the molecular machinery of the cell: loosely attached to the virus are chains of a protein called ubiquitin, which interacts with a cellular enzyme known as HDAC6; at the same time, HDAC6 binds to components of the cell's skeleton and to motor proteins, pulling the capsid into pieces so that it can be degraded by the cell's waste disposal machinery. Opening up the capsid releases the genetic material of the virus inside the cell, facilitating viral infection. To test whether interfering with HDAC6's interaction with ubiquitin could hinder flu infection, Longlong Wang and his colleagues in the Matthias group screened DARPins, a class of synthetic proteins that can bind to a variety of targets.