The Journal of Cell Biology

Intracellular transport is essential for neuronal organization, yet how motor proteins achieve cargo selectivity remains incompletely understood. Kinesin-2 motors transport diverse cargos through the heterotrimeric KIF3/KAP3 complex, but whether variations in assembly composition contribute to functional specificity has been unclear. This study provides evidence for heterogeneity in neuronal KIF3…

The spatial organization of chromatin at the nuclear lamina contributes to genome structure and gene regulation. Mechanical inputs are increasingly recognized as key regulators of nuclear architecture, and understanding how they control genome-lamina interactions and influence diseases associated with the nuclear lamina remains unclear. To understand the role of lamin proteins and the cytoskeleto…

A defining feature of meiosis is the synaptonemal complex (SC), a zipper-like protein structure that forms between homologous chromosomes to regulate their recombination and segregation. Historically viewed as an enigmatic electron-dense scaffold, the SC is now recognized as a dynamic signaling platform that coordinates key meiotic processes. Here, we review recent advances in understanding SC st…

Collective cell invasion underlies organ development, epithelial repair, and cancer metastasis. "Leader cells" remodel ECM, sense guidance cues, reorganize their cytoskeleton, and coordinate follower cells, but the molecular programs enabling these functions remain unclear. Here, we present a stage-specific transcriptomic dataset of the Caenorhabditis elegans gonadal leader cell, the distal tip c…

Microtubule acetylation is implicated in regulating cell motility, yet its physiological role in directional migration and the underlying molecular mechanisms have remained unclear. This knowledge gap has persisted primarily due to a lack of tools capable of rapidly manipulating microtubule acetylation in actively migrating cells. To overcome this limitation and elucidate the causal relationship …

The cell biology of tissues challenges us to understand how fundamental processes found in free living as well as communal cells are coordinated to achieve complex patterns of behavior on the scale of cellular populations. In this issue, Soffer et al. (https://doi.org/10.1083/jcb.202502071) reveal how cell-cell adhesion co-opts the spectrin membrane skeleton to achieve this goal in the epidermis …

How the nucleolus recovers from acute proteostatic stress, particularly in multinucleate syncytia, remains poorly understood. In the highly polarized hyphae of the model filamentous fungus Magnaporthe oryzae, we uncover a novel stress-induced spatial quality control pathway that promotes the inheritance of rejuvenated nucleolar material during nuclear division. This pathway discriminates between …

Lysosomes are subject to perturbations that can cause damage to their limiting membrane. Osmotic shifts, pore-forming toxins, and the growth of luminal polymers or pathogens all stand to increase lysosomal membrane tension and/or disrupt the bilayer. In some contexts, this leads to lysosomal rupture and cell death. Here, we describe a mechanism that enables lysosomes to sense and respond to acute…

The conserved Ypt/Rab GTPases regulate all steps of the intracellular transport pathways. In yeast and human cells, Ypt1/Rab1 regulate early steps of secretion and autophagy, whereas Ypt31/Rab11 regulate a late step in secretion, and the TRAPP complexes act as their activators. The Ypt and transport step specificity of TRAPP complexes is currently controversial. Here, we use in vivo analyses of m…

Membrane contact sites between organelles are important for maintaining cellular lipid homeostasis. Members of the recently identified family of bridge-like lipid transfer proteins (BLTPs) span apposing membranes at these contact sites to enable the rapid transfer of bulk lipids between organelles. While the VPS13 and ATG2 family members use organelle-specific adaptors for membrane targeting, the…

Tetraspanins are integral membrane proteins that play a crucial role in organizing and regulating cellular signaling by serving as scaffolds that compartmentalize receptors and other signaling molecules within membrane microdomains. Here, we report how the tetraspanin CD82 modulates the molecular organization and signaling of the EGF receptor (EGFR), a key molecule involved in cellular proliferat…

Bridge-like lipid transfer proteins (LTPs) contain a repeating β-groove domain and long hydrophobic grooves that act as bridges at membrane contact sites (MCSs) to efficiently transfer lipids. Atg2 is one such bridge-like LTP essential for autophagosome formation, during which a newly synthesized isolation membrane (IM) emerges and expands through lipid supply. However, studies on Atg2-mediated l…

Collective chemotaxis is often viewed through a mesenchymal lens, emphasizing peripheral polarity and force generation. In this issue, Diaz and Mayor (https://doi.org/10.1083/jcb.202507211) reveal that epithelial-like neural crest clusters achieve directed chemotaxis through a junction-centered strategy that redistributes polarity, contractility, and traction forces internally.

In this issue, Almasoud et al. (https://doi.org/10.1083/jcb.202504139) report a surprising finding that epithelial cell polarity is present in a tissue with no known polarized function, in a cell type that was assumed to show a distinct lack of such polarity-the mesenchymal cells of the Drosophila fat body. Exceptions such as this help to broaden our understanding of the use of regulators and pat…

documents a direct connection between actin filaments and cytoplasmic movements.The primary data showing movements in cell-free extracts of Amoeba proteus were recorded on 16-mm movie film and shown at the 1968 Annual Meeting of the American Society for Cell Biology (ASCB; Pollard and Ito, 1968).However, no technology was available at the time to include this data in the paper.This addendum inclu…