Linking membrane dynamics and trafficking to autophagy and the unfolded protein response

Cellular stressors typically induce two protective counter‐responses—autophagy and the unfolded protein response (UPR). It is conceivable that these two endoplasmic reticulum (ER) membrane‐based processes would intersect/interact somehow with the constitutive housekeeping process of exocytic membrane traffic from the ER. How exactly might this occur? Recent evidence indicates that a conserved Rab protein, Rab1/Ypt1p, has functional roles in UPR and autophagy. This molecular switch and its associated effectors may therefore serve to link up a network of cellular responses to stress through changes in membrane dynamics and protein turnover. The notion provides further explanations as to why elevation of Rab1/Ypt1p levels could counter the cytotoxicity of α‐synuclein, and a similar mode of protection may well be at work against other stresses. J. Cell. Physiol. 228: 1638–1640, 2013. © 2013 Wiley Periodicals, Inc.