Paul et al. use cryo-ET to show that microtubules can contain actin filaments in their lumen. Two types of F-actin structure are distinguished, Class I and Class II, with slightly different helical symmetries and outer microtubule diameters. They call these filaments microtubule lumenal actin (ML-actin).

Cancer cell dissemination is facilitated by small actin-rich plasma membrane protrusions called invadopodia. Pedersen et al. now show that invadopodia maturation and function depend on contact site formation between the endoplasmic reticulum and late endosomes, which promotes translocation of the latter to growing invadopodia.

Trafficking of matrix metalloproteinases (MMPs) through the Golgi remains enigmatic in the field. Pacheco-Fernandez et al. find that nucleobindin-1 (NUCB1), a cis-Golgi localized Ca2+-binding protein, plays a major role in this process by binding to MMPs, regulating their intra-Golgi trafficking, and thereby modulating cell invasion and matrix degradation.

Autophagy selectively degrades a wide range of cellular components to regulate cellular functions or maintain cellular homeostasis. Tomioka et al. reveal that the nuclear pore complex and nucleoporins are degraded by selective autophagy upon inactivation of Tor kinase complex 1 in Saccharomyces cerevisiae.

Autophagy requires the synthesis of PI(3)P and the conjugation of LC3 to the phagophore membrane. We reconstituted these two reactions and their coupling by WIPI2 and showed that positive feedback between PI3KC3-C1 and WIPI2 leads to rapid LC3 lipidation by the ATG16L1 complex.

Sas4 is a conserved basal body assembly protein. Here, Ruehle et al. describe a previously unknown link between basal bodies and the control of cell division by Hippo signaling molecules that depends on Sas4.

To segregate chromosomes, the mammalian spindle must generate and respond to force. How it does so remains poorly understood. Pulling on the spindle using microneedles, Long et al. show that it can locally dissipate sustained force by regulating microtubule dynamics and breakage, thereby preserving global spindle structure.