Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, New York, NY 10016, USA. ron@saturn.med.nyu.edu
The long-awaited structure of the effector portion of IRE1, the endoplasmic reticulum stress transducer, is published in this issue of Cell (Lee et al., 2008). This structure provides new insight into the mysterious coupling of kinase and endoribonuclease activities in the oldest, most-conserved branch of the unfolded protein response in eukaryotes.