Issues

Summary: Rod and cone photoreceptors contain a unique light-sensitive outer segment compartment that has a central role in phototransduction, the visual cycle, membrane renewal, protein trafficking and many retinal degenerative diseases.

Summary: In this Commentary, we review current evidence supporting intracellular PtdIns(4,5)P₂ signaling, with a focus on PtdIns(4,5)P₂ regulation of endolysosomal trafficking and protein recycling, as well as autophagic membrane trafficking.

Highlighted Article: During membrane stretching in yeast protoplasts, eisosomes disassemble to release membrane invaginations and to facilitate surface area expansion.

Summary: Ciliary trafficking of polycystin-1 is regulated by multiple motifs at its C-terminus and by polycystin-2 but not by cleavage at its G-protein-coupled receptor proteolytic site.

Highlighted Article: The STIM1-interacting protein junctate generates Ca²⁺ hotspots that boost phagocytosis independently of STIM1 by promoting Ca²⁺ release from ER stores rather than by gating phagosomal Ca²⁺ channels.

Summary: The mechanism of ERK1c translocation to the Golgi in mitosis is elucidated, combining several independent Golgi-regulating processes into one coherent pathway.

Highlighted Article: LPS induces clustering of CD14 in the plasma membrane, which triggers PI(4,5)P₂ generation in rafts that is required for maximal pro-inflammatory signaling of TLR4.

Summary: Proteins containing defective transmembrane domains are removed from the endoplasmic reticulum through a specific mechanism that depends upon the ubiquitylation of cytoplasmic lysine residues.

Highlighted Article: Membrane recruitment of the endosomal effector protein Rabaptin5 is shown to be mediated by both Rabex5 binding to ubiquitylated cargo and Rab4 to activate Rab5 in a feed-forward manner.

Summary: Plectin-arranged vimentin scaffolds keep actomyosin contractility ‘in-check’ and maintain cell–cell junction homeostasis, providing a new perspective on cytoskeleton-controlled vascular permeability.

Highlighted Article: The C-terminal Tyr residue of FUS can be phosphorylated by members of the Src kinase family. Phosphorylated Tyr526 impairs the interaction of FUS with transportin 1 and, potentially, its nuclear import.

Summary: p150^glued stabilizes COPII pre-budding complexes on ER exit sites in a microtubule-independent manner, and it coordinates protein sorting, carrier formation and long-range transport events.

Summary: Using mammalian cells and Drosophila, we have identified a new mitochondrial pool of the cell cycle regulator cyclin E that can be modulated by Drp1 to control cell proliferation.

Summary: A transient interaction between Cdc42 and GRAF1 drives endocytic turnover at the leading edge, and controls the transition essential for endosomal maturation of plasma membrane internalised by this mechanism.

Summary: The interaction of NRIP with CaM results in the induction of slow myosin gene expression and mitochondrial activity, as well as the balancing of Ca²⁺ homeostasis; thus, loss of NRIP leads to muscle dystrophy.

Summary: Oxidized RNA is controlled by a Calvin cycle enzyme subunit and is compartmentalized in chloroplasts and human cells.

Summary: In yeast, α-arrestins bind the Rho1 GTPase and regulate internalization of selective cargo through the clathrin-independent endocytic pathway.

Summary: Activation of m1 muscarinic acetylcholine receptor is well known to suppress KCNQ channel activities, but it also induces surface transport of KCNQ channels through a CRMP-2 mediated mechanism.