Su et al. show that SUMOylation stabilizes bioriented kinetochore–microtubule attachments in mitosis to allow timely anaphase onset. They identify the shugoshin pericentromeric adaptor protein and the chromosome passenger complex as SUMOylation targets, which lead to dampening of error correction pathways.
A BLOC-1–AP-3 super-complex sorts a cis-SNARE complex into endosome-derived tubular transport carriers
Bowman et al. show that in melanocytes, the vSNARE VAMP7 is sorted from endosomes into tubular membrane transport carriers bound for maturing melanosomes in a complex with the tSNARE syntaxin 13 via redundant recognition of each SNARE by an AP-3–BLOC-1 super-complex.
In myeloproliferative neoplasms, oncogenic transformation involves mutations in the ER chaperone calreticulin (CRT) that drive aberrant activation of the thrombopoietin receptor/myeloproliferative leukemia protein (Mpl). Venkatesan et al. here describe the molecular mechanism underlying mutant CRT-mediated constitutive activation of Mpl.
ER-mitochondria contacts respond to cellular stress. Chai et al. reveal that in response to hypoxia, USP19, an ER-resident deubiquitinase, accumulates at ER-mitochondria contact sites where USP19 deubiquitinates and stabilizes FUNDC1, thereby promoting Drp1 oligomerization and subsequent hypoxia-induced mitochondria division.
Nakayama et al. show that Daple is responsible for the increased microtubule (MT) density on the Frizzled side of the apical junctional complex (AJC) in multiciliated cells via bundling and stabilizing MTs and mediating interactions between MTs and the AJC.
Yang et al. develop a proteomics-based approach to systematically isolate asymmetrically localized proteins in Dictyostelium, through which they identify an LRR domain–containing protein named Leep1. Their results reveal that the spatiotemporal coordination of PIP3 signaling, Leep1, and Scar/WAVE complex modulates protrusion morphogenesis at the leading edge of cells.
Deliz-Aguirre et al. examine the molecular dynamics of interleukin 1 receptor signaling. Receptor sensing of IL-1 triggers the oligomerization of MyD88 and formation of the Myddosome signaling complex. The formation of a MyD88 oligomer of a requisite size serves as a threshold to active downstream signaling.
Ali-Murthy et al. show that during Drosophila oogenesis, several nurse cell nuclei move into the oocyte through a channel that opens when nurse cells and oocyte transiently fuse, and that nuclear transfer/elimination is essential for oocyte maturation and embryonic viability.
Pal et al. discover that podosomes and invadopodia ubiquitously recruit membrane-bound DNase X, which readily degrades extracellular double-stranded DNA. The authors also show that macrophages, in response to immunogenic materials, form podosomes that degrade bacterial DNA on surfaces.
Centromeric transcription is critical for proper centromere function, but its exact role remains elusive. By manipulating the activity of centromeric transcription, Chen et al. report that a major function of centromeric transcription in human cells is to maintain centromeric cohesion.
Nuclear pore complexes mediate nuclear transport and are highly modified with O-linked N-acetylglucosamine (O-GlcNAc) on FG repeat domains. Using a new quantitative live-cell imaging assay, Yoo and Mitchison demonstrate acceleration of nuclear import and export by O-GlcNAc modification.