Fig. 5.
Model for staged activation of IRE1. The model depicts that several steps mediate IRE1 activation including BiP release, initial intramolecular autophosphorylation, dimerization, and dimerization-induced trans-autophosphorylation (see Discussion for details). Increasing degrees of IRE1 autophosphorylation cause higher levels of RNase activity indicated as darker shades of brown.