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Cytokinesis relies on central spindle organization and provides a spatial landmark for lumen formation. Here, the authors show that intraflagellar transport proteins are required for the localization of the cytokinetic regulator Aurora B and subsequent cleavage furrow ingression and lumen positioning.

Arnaud Echard discusses two studies that uncovered a key role for the ESCRT machinery in cytokinesis.

To stop bleeding from an injured vessel, platelets adhere and form a clot despite high shear stress from the flow. Here, the authors show that platelet actin disassembly is a key step that enables a receptor to translocate to membrane lipid rafts, enhancing its adhesive function under shear stress.

Bunel et al. show that mitochondria behave as asymmetric fate determinants in vertebrates in vivo. Forcing their unequal segregation during mitosis is sufficient to drive premature neural differentiation of the daughter inheriting the smallest pool.

Completion of cell division requires severing both the microtubules and the plasma membrane that connects daughter cells. Here, the authors show that branched actin regulates ESCRT localization to promote the microtubule cut, which happens before membrane scission.

ESCRT filaments drive the final abscission between two daughter cells but how they physically interact with the membrane is unclear. Using proteomics, the authors show that syndecan-4/syntenin/ALIX couples the ESCRT machinery to the abscission site and thus promotes efficient abscission.

Cytokinetic abscission relies on the local constriction after cytoskeleton disassembly, but it is not known how the actin filaments are disassembled. Here, the authors show that the redox enzyme MICAL1 is recruited by Rab35 and induces oxidation-mediated depolymerization of actin, which is required to recruit ESCRT-III and complete abscission.

Establishment and maintenance of apico-basal polarity in epithelial organs needs to be tightly coupled with cell division. Here the authors show that the Rab35 GTPase tethers intracellular vesicles containing key apical determinants at the cleavage site, connecting cytokinesis to apico-basal polarity.

The ESCRT (endosomal sorting complex required for transport) machinery is responsible for scission of the cytokinetic bridge that connects daughter cells at the end of mitosis. Specific endosomes are now found to mediate local bridge constriction and actin clearance in human cells, which contribute to the recruitment of ESCRT components at the abscission site.

Methylation of CHMP2B regulates abscission timing by modulating ESCRT-III dynamics during cytokinesis. This methylation also plays a role in HIV-1 budding, highlighting the broader significance of ESCRT-III methylation.

Broadly neutralizing antibodies (bNAbs) neutralize HIV-1 and exert Fc-dependent activities against infected cells. Here, Dufloo et al. show that bNAbs also block HIV-1 release by trapping viral particles at the surface of infected cells.

Charcot-Marie-Tooth (CMT) is an inherited peripheral neuropathy. Here, the authors show that Rab35 forms a complex with genes implicated in CMT, MTMR13 and MTMR2, which regulates myelin growth by controlling mTORC1 signaling through lipid turnover.

The non-processive motor, myosin II, is shown to be an effector of the Golgi-associated Rab6 GTPase. The acto-myosin machinery is involved in the fission of transport carriers from Golgi membranes.

The PtdIns(4,5)P₂ 5-phosphatase OCRL, mutated in Lowe syndrome, is implicated in trafficking and associates with Rab GTPases. OCRL function is now extended to cytokinesis, where it controls abscission of the intercellular bridge downstream of Rab35 through the local reduction of both PtdIns(4,5)P₂ levels and actin accumulation.

Some p53 mutants promote invasive migration of cancer cells and metastasis of tumours in vivo. However the key mechanistic details behind these phenomena remain unclear. Here the authors propose a non-cell autonomous mechanism involving fibroblasts, whereby mutant p53-expressing cancer cells activate an exosome-mediated mechanism that influences integrin recycling in fibroblasts, thus influencing extracellular matrix remodelling to favour cancer cell invasion and migration.

Actin and microtubules play important roles in Golgi structure and function but how they are connected is poorly understood. Here the authors show that KIF20A is involved in the fission process and, in association with Myosin II, serves to anchor RAB6 on Golgi/TGN membranes near microtubules nucleating sites.