Chromosome segregation is triggered by separase and is abrupt and largely synchronous. Williams et al. show that synchronous chromosome segregation does not require separase-mediated positive feedback and that slight asynchrony may be unavoidable due to stochastic effects when only a few cohesin complexes remain at the time of sister chromatid separation.

Eosinophils are associated with infection and pathological fibrosis. However, healthy small intestinal villi harbor dense populations of these granulocytes. Here, Petrova et al. show that eosinophils convert PDGFRβ+ fibroblasts to specialized villus smooth muscle cells, driving a developmental program for postnatal intestinal remodeling and maturation.

Guerrero-Fonseca et al. provide evidence for a cellular cross talk through which neutrophils transfer proteases into endothelial cells to degrade cortactin, thus facilitating breaching of the vascular endothelium during inflammation.

Covill-Cooke et al. find that the ERMES lipid-transporting complex, long-thought to be an obligate heterotetramer, can be replaced by only one component: mitochondrially tethered Mmm1.

Cook et al. show that macrophages sense cell volume disruption as a danger signal promoting transcriptional reprogramming and inflammatory responses via type I interferon signaling. Cell swelling synergizes with pathogen-sensing pathways to amplify inflammation, and macrophage volume regulation coordinates inflammatory responses during influenza infection and influences the development of the cytokine storm.

Actin network organization plays a critical role in regulating animal cell shape. We examined the Drosophila synaptotagmin-like protein (Btsz) in early embryo nuclear divisions, identifying a role for regulating pseudo-cleavage furrow stability. We showed that Btsz bundles actin filament networks in vitro.

Das and Chavez et al. demonstrate that in D. melanogaster, the histone chaperone NASP indirectly affects the nuclear import and chromatin deposition of H3. Their findings reveal a cytoplasmic function for NASP in preventing H3 aggregation in vivo. Live imaging in Drosophila embryos reveals that the H3 chaperone NASP does not directly affect H3 nuclear import or export rates. Reduced H3 levels in NASP-deficient embryos indirectly affect nuclear import and H3 deposition into chromatin. In vivo, cytoplasmic NASP prevents H3 aggregation and H3 aggregation and degradation are developmentally separable events.