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Théry and colleagues find that the centrosome can participate in actin-filament assembly in a manner that is mediated by WASH and Arp2/3 and requires the presence of pericentriolar material.

Microtubules can self-repair in vitro in response to stress. Théry and colleagues now show that such repair can occur in cells, as free tubulin dimers can be incorporated into a damaged microtubule lattice to promote rescue events.

External forces can make cells undergo large, irreversible deformations. It emerges that stretched mammalian cells grown in vitro can enter a state called superelasticity, in which large, reversible deformations occur.

The combined role of cellular junctions and actomyosin networks in tissues remains unclear. Here, the authors identify a tissue-scale star-shaped network of actomyosin that preserves cell shape, limits migration, and coordinates the intestinal epithelium.

Cells migrate en masse to generate and renew tissue — but inadequate resolution and incompatible timescales obscure the mechanism behind this migration. A unique approach reveals that stress mediates collective motion by propagating in a wave from the leading edge to the population centre.

Microtubules respond to mechanical compression by deforming, becoming more stable, which results in CLASP2 recruitment to the distorted shaft—a process crucial for cell migration through confined spaces.

The fabrication of microchips with vertically stacked circuits is challenging because they require arrays of electrical interconnections between the circuits, where accessibility is limited. An approach to generate conductive, mechanically stable plug-and-socket interconnections through three-dimensional actin-filament self-organization and selective metallization offers a potential solution to this problem.

The orientation of the cell division axis is critical for normal growth and development as it determines the fate of future daughter cells; and the extracellular matrix to which cells adhere to plays a role in determining the orientation of the division axis. Here Bornens and colleagues present a combination of experimental and quantitative theory to show that spindle orientation is controlled by cortical force generators; a simple model based on pulling forces exerted by force generators on spindle microtubules can quantitatively describe spindle orientations in many different geometries.

Actin filaments are a principal component of the cell cytoskeleton. Using micropatterning methods, physical influences on the growth of highly ordered actin structures are investigated. The spatial organization of actin nucleation sites is discovered to play an important role in establishing the architecture of actin networks.

Molecular motors destroy a microtubule lattice as they walk on it, but it is now shown that a self-healing process incorporates new dimers in the damaged regions and prevents microtubule disassembly.

Microtubules vary their length by gaining and shedding tubulin dimers dynamically at both ends. But evidence now suggests that dimers may also be incorporated into the middle of the shaft—calling into question existing models of growth dynamics.

The mechanism of stress fibre assembly by the coalescence of actin filaments in the cell cortex has now been found to account for the transmission of mechanical forces throughout the entire cell along stress fibres.

Experiments show that the progressive softening of microtubules under mechanical stress results from the enlargement of pre-existing structural defects, and that the incorporation of tubulin dimers can restore the microtubule’s initial stiffness.

Substrate-rigidity-dependent microtubule acetylation is now shown to be triggered by mechanosensing at focal adhesions, and in turn controls the mechanosensitivity of Yes-associated protein (YAP) translocation, focal adhesion distribution, actomyosin contractility and cell migration.

Protrusive cellular structures contain a heterogeneous density of actin, but whether this influences motility is not known. Using an in vitro system and modelling, here the authors show that local actin monomer depletion and network architecture can tune the rate of network growth to impose steering during motility.

Despite the constant renewal of their components, cellular actin networks maintain their overall appearance, through a subtle balance of filament assembly and disassembly. This balance is key to the remodelling of cellular architecture. We discuss the significance of in vitro reconstitutions in deciphering the complexity of actin regulation.

Cell polarity is marked by re-orientation of the centrosome, but the mechanisms governing centrosome polarization are poorly understood. Here Obino et al. show that in lymphocytes centrosome-associated Arp2/3 nucleates actin that tethers the centrosome to the nucleus; activation depletes Arp2/3 from the centrosome and frees it from the nucleus.

Cell metabolism ensures that cell dynamics and continued renewal are supported by a constant flow of matter that consumes energy. A new study shows that cell metabolism is sensitive to mechanical cues, revealing that the level of cell contraction modulates the production and storage of lipids, which could serve as fuel for energy production.

Faessler and colleagues analyse the distinct properties of β₁ and α_v integrin subclasses, and provide insight into the different protein compositions, signalling activities and contributions to rigidity sensing of adhesion sites anchored by each integrin subtype.

Theoretical modelling in combination with measurements of tension and shape in epithelial domes of controlled geometry reveals a plateau of tension in tissue that is maintained by heterogeneous strain across cells.

Micropatterning of cryo-EM grids enables controlled adhesion of mammalian cells for cryo-ET-based structural studies. This approach leads to reproducible cellular morphology and improves focused ion beam thinning of cells for in-cell structural analyses.

Cancer cells often have extra centrosomes, a paradox considering the detrimental effect extra centrosomes usually have on cell division; a study of human cells reveals that extra centrosomes can promote cancer cell invasion phenotypes through a pathway involving increased microtubule nucleation and Rac1 activity.

Acetylation of α-tubulin on lysine 40 is associated with microtubule stability. In vitro experiments by Portran et al. show that tubulin acetylation reduces lateral interactions, increasing microtubule flexibility and resistance to mechanical stress.

This Perspective argues that tissue-manufacturing approaches relying on directed self-organization will enable the production of functional tissues with complex biological features.