摘要
In order to survive, all organisms must guard against viral infections. Recognition of viruses is accomplished via multiple sensors. Many mammalian proteins can recognize viral products, such as double-stranded RNA （dsRNA）, yet few of them are known to induce interferon, the central antiviral messenger. Since interferon is indispensable for successful antiviral defense [1], the interferon-inducing sensors have been of particular interest. However, a clear understanding of such sensors has been elusive, and the first well-established sensor family, the toll-like receptors （TLRs）, was described relatively recently [2]. Antiviral TLRs are positioned in the endosomes, where they report the appearance of viral genetic material （DNA, single-and double-stranded RNA）. However, the question of potential virus sensors in the cytoplasm was left open. Given the particular effectiveness ofintracellular dsRNA at inducing interferon, it was suspected that dsRNA-binding sensor molecules would be found in the cytoplasm.
