Researchers Create Models to Uncover How Cells Deal with Self-Directed Gene Silencing

It’s been postulated that the mechanism of RNAi developed in cells as a means to fight off viral invaders and transposable elements. Essentially, this makes it a kind of cellular immune system, according to the authors of a paper published in this week’s Proceedings of the National Academy of Sciences. But this hypothesis, while reasonable, raises the question of how the RNAi system is able to deal with the equivalent of an autoimmune disorder, a system error where silencing is directed to a cell’s own genes.