Mitochondria form a network that is constantly remodeled by fission and fusion. Abrisch et al. show that fission and fusion machineries converge at ER membrane contact sites (MCSs) to provide a unified platform where fission and fusion are coordinated to balance mitochondrial dynamics and morphology.

Nijenhuis et al. developed a robust optogenetic toolbox to reversibly reposition organelles in populations of cells with minimal adverse effects on endogenous transport. This work opens new opportunities to dissect intracellular transport and spatial cell biology.

Nup188 is part of the nuclear pore complex scaffold that is specifically required for heart development. As shown by Vishnoi et al., Nup188 also moonlights as a centrosome protein by binding directly to Cep152 and contributing to centriole duplication.

ER arrival sites (ERAS) that capture retrograde Golgi-to-ER COPI vesicles have not been well characterized. Roy Chowdhury et al. use the budding yeast Pichia pastoris to show that ERAS are physically and functionally linked to ER exit sites (ERES).

Stem cell activity has to be regulated throughout adult life to maintain tissue homeostasis. Li et al. find that the membrane-associated kinase Gilgamesh (Gish/CK1γ) restricts JNK signaling and Drosophila intestinal stem cell proliferation by phosphorylating and destabilizing Rho1.

Itakura et al. identify a protein quality control system for aberrant extracellular proteins, including misfolded proteins and amyloid β. This extracellular proteostasis pathway involves the cell-surface heparan sulfate receptor, which mediates internalization of aberrant extracellular proteins in complex with an extracellular chaperone.

Zewe et al. develop approaches to map the subcellular distribution of the major phospholipid, phosphatidylinositol (PI), revealing that the lipid is present in most membranes except for plasma membrane, where it is found mainly as PI4P and PI(4,5)P2.