RNA exosomes keep endogenous RNA under the radar

摘要

All eukaryotic cells must react to external and internal threats that violate their integrity. One common threat is the intrusion of DNA and RNA from pathogens, such as viruses. Eukaryotic cells have cytosolic sensors of viral nucleic acids that initiate host defense, including cytokine responses. However, these sensors should not be stimulated by endogenous nucleic acids that reach the cytosol. In this issue of Nature Immunology, Eckard et al. show that a component of the RNA exosome, SKIV2L, meets this need by degrading modified endogenous RNA that is generated during the unfolded protein response via RNA decay dependent on the endonucleaseIRE-1 (ref. 1).