After invading a cell, some viruses cozy up to it's internal membranes before reproducing, but scientists haven't been sure why. Now they've seen that one such microbe, the flock house virus, reproduces in cocoons within the membranes.
The cocoons are havens where the virus can replicate safe from the cell's defenses, says Paul Ahlquist at the University of Wisconsin–Madison. But before the virus can hide itself, it must produce proteins that make up the pouches. "The early phase of [viral] replication is a point of significant vulnerability," says Ahlquist, who led the research. Drugs that interfere with the cocoons' proteins or otherwise thwart the creation of the cavities could leave the viruses exposed to attack by the cell, Ahlquist says.