“HCPro, the RNA silencing suppressor (RSS) of viruses belonging to the Potyvirus genus in the Potyviridae family, is a multifunctional protein presumably involved in all essential steps of the viral infection cycle. Recent studies have shown that Plum pox potyvirus (PPV) HCPro can be successfully replaced by Cucumber vein yellowing ipomovirus P1b, a sequence unrelated RSS from a virus of the same family. In order to gain insight into the requirement of a particular RSS to establish a successful potyviral infection, we tested the ability of different heterologous RSSs from both plant- and animal-infecting viruses to substitute HCPro. Making use of engineered PPV chimeras, we show that PPV HCPro can be functionally replaced by some, but not all, unrelated RSSs, including the NS1 protein of the mammalian-infecting Influenza A virus.”
Fascinating stuff: shows how promiscuois, or possibly how universal, the machinery for avoiding silencing is – and how funadamental to the life cycles of viruses. One could almost argue “virus altruism”?
See on vir.sgmjournals.org