«The Flu Virus»
In order to proliferate, influenza viruses use the cells in the respiratory passages: they channel their hereditary information into the cells, which use this information to produce new viruses. The influenza viruses dock to the cell surface and enter the cell interior in the form of small vesicles. They free themselves from the bubbles (endosomes) and then release their genetic information. This is not easy because it is protected in a solid capsule.
Indranil Banerjee, Yasuyuki Miyake and Yohei Yamauchi have found out how the capsule is broken: the viral marker sticks on the outside to the old capsid, which is to be picked up as bulky waste. These markers are called ubiquitin. The cell binds the capsule via the marker for garbage and breaks it with the substance HDAC6 and eliminates it. HDAC6 binds to ubiquitin and the capsule, causing it to tear. The viral genomic segments become free, enter the cell nucleus, and the cell produces hundreds of new viruses.
Now the researchers are looking for a substance that can block HDAC6 so that ubiquitin no longer can bind. This substance could be the basis for a new influenza medication.
Influenza A virus uses the aggresive processing machinery for host cell entry. Indranil Banerjee, Yasuyuki Miyake, Samuel Philip Nobs, Christoph Schneider, Peter Horvath, Manfred Kopf, Patrick Matthias, Ari Helenius, Yohei Yamauchi. Science 2014; 346: 473-477.