Grey et al. discover a mechanism by which the epithelial-specific ER stress sensor IRE1β acts as a negative regulator of IRE1α. IRE1β interacts directly with IRE1α to suppress XBP-1 splicing and modify the unfolded protein response to endoplasmic reticulum stress in intestinal epithelial cells.

GDPGP1 and its C. elegans homologue mcp-1 are identified as novel stress-responsive genes in neuronal cells. Stress-induced down-regulation of GDPGP1/mcp-1 reduces cellular glycogen levels and contributes to hypoxia sensitivity and neurodegeneration across species.

Schormann et al. provide a reference library of confocal micrographs of key organelles in live epithelial cells as landmarks and a derived feature set that can be used to assign protein localization throughout the secretory pathway and to key organelles via a quantitative unbiased image-based classifier.

Coat disassembly, driven by the Hsc70 “uncoating ATPase” and mediated by auxilin, occurs within seconds after vesicle release. Using single-molecule imaging, He et al. find that auxilins are absent from assembling pits. Therefore, Hsc70 is not responsible for the clathrin exchange during pit formation.

Nucleus centering in mouse oocytes depends on a gradient of actin-positive vesicle persistence. Modeling coupled to 3D simulations and experimental testing of predictions coming from the simulations demonstrate that this gradient nonspecifically centers large objects during prophase I and meiosis I in oocytes.

The authors show the dual regulation of phagosomal degradation and migration of Drosophila macrophages by Trpml, a lysosomal calcium channel. Trpml promotes cell migration by activating actomyosin contractility but supports phagosomal degradation through a myosin-independent mechanism.

Clathrin stabilizes microtubules and promotes chromosome alignment during mitosis. Rondelet et al. show that the clathrin–adaptor interaction mechanism is repurposed to recruit GTSE1 to the spindle, which inhibits the microtubule depolymerase MCAK and promotes chromosome alignment by stabilizing nonkinetochore microtubules.