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.

The spindle assembly checkpoint requires recruitment of Mad1-C-Mad2 to unattached kinetochores but also Mad1 binding to Megator/Tpr at nuclear pore complexes during interphase. Cunha-Silva et al. provide evidence that this spatiotemporal redistribution is due to Mps1-mediated dissociation of Mad1 from Megator/Tpr during prophase, which is critical for Mad1-C-Mad2 accumulation at unattached kinetochores and for the accuracy of chromosome segregation in vivo.

This study reveals a novel role of hemidesmosomes in resisting actomyosin-generated cellular tension, which is dependent on mechanical coupling of focal adhesions to hemidesmosomes and inhibition of mechanosensitive signaling. Furthermore, through their ability to influence cellular tension, hemidesmosomes also control the localization of αvβ5 in flat clathrin lattices.

Lee et al. show that the local abundance of the chloride importer NKCC1 and timely emergence of GABAergic inhibition are modulated by proteasome distribution, mediated through interactions of proteasomes with the proteasome adaptor Ecm29 and the axon initial segment scaffold protein ankyrin G.

Rossi et al. describe a novel assay for exocyst in-vesicle tethering. In this assay, gain-of-function mutants in the Exo70 subunit of the exocyst, which bypass Rho/Cdc42 activation in vivo, stimulate vesicle tethering. Single-particle EM studies reveal a structural change responsible for the gain of function.

Escape of large macromolecular complexes induces mechanical stress, which may threaten ER membrane integrity. How the ER responds to this threat remains unknown. Chen et al. demonstrate that the ER morphogenic protein reticulon (RTN) protects ER membrane integrity during ER escape of these complexes.