Cytoskeleton

Tubulin, the building blocks of microtubules, can be removed from the microtubule wall by mechanical forces. Using single-molecule methods, the authors show that tubulin partially unfolds prior to its removal and determined the tubulin-extraction force.

Using the Drosophila pupal notum, the authors demonstrate that the disassembly of microtubules by effector caspases initiate cell extrusion independently of actomyosin regulation, thus providing insights into how caspases orchestrate dying epithelial cell expulsion.

Mycobacterium marinum, a close relative of Mycobacterium tuberculosis, polymerizes host actin at the bacterial surface to drive intracellular movement and cell-to-cell spread during infection. Here, Hill & Welch identify an M. marinum surface protein that binds to and activates the host protein NWASP to stimulate actin polymerization and drive bacterial actin-based motility.

Williams et al. report that, upon TORC1 inhibition in yeast, mRNA of the chaperone protein ADC17 is localized to cortical actin patches where its translation is enhanced upon stress.

Drubin et al. use three different advanced imaging approaches to show that actin assembles preferentially at stalled clathrin-mediated endocytosis sites, where the actin pulls vesicles into the cell asymmetrically, as a bottle opener pulls off a cap.

Haque et al. report that the Hedgehog pathway kinesin KIF7 binds the transcription factor GLI via electrostatic coiled-coil interactions, and synergy between KIF7 and GLI underlies the recruitment of both proteins to microtubules and the cilium tip.