Issues

Parker et al. show that the Ena/VASP protein, EVL, complexes with the I-BAR protein, MIM/MTSS1, to drive filopodial protrusion from dendrites during neurodevelopment. These dendritic filopodia are precursors of dendritic spines and are critical for guiding neural connectivity. The findings presented here further our understanding of neural plasticity, which is compromised in several neurodevelopmental disorders.

Limar et al. show that the yeast protein Svf1 localizes to the cis Golgi apparatus via an N-terminal amphipathic helix. Svf1 directly binds ceramides and is necessary to maintain appropriate levels of complex sphingolipids, most likely by transporting ceramides between the ER and the Golgi apparatus.

Dynein-driven chromosome movement facilitates chromosome synapsis in prophase I of meiosis, which is essential for genetic exchange and completion of meiosis. Dynein-1 is recruited by KASH5 in the outer nuclear envelope. The authors show that KASH5 is an activating dynein adaptor and characterize the KASH5–dynein interaction.

Mascarau et al. demonstrate the relevance of HIV-1 infection of tissue-resident macrophages by fusion with infected CD4⁺ T cells and show that this process is modulated by the macrophage activation state and is under the control of the CD81/RhoA/Myosin axis.

Chromosome alignment and segregation in mitosis are tightly regulated. This study shows that PP6 limits the activity of Aurora A toward the kinetochore protein NDC80. NDC80 phosphorylation by Aurora A is restricted to microtubule-attached, checkpoint-silenced kinetochores and is important for regulation of both spindle size and chromosome segregation.

Using kinetic trafficking assays, genetics, and secretomics, Pereira, Stalder et al. demonstrate the role of the exocyst complex in the secretory pathway. Exocyst subunits co-localize with post-Golgi carriers and their abrogation results in intracellular cargo accumulation in various cell types.

Liu et al. show that precursors of specific GPI-anchored proteins, such as CD55, function with an ER-resident lipid homeostasis regulator ARV1 to upregulate GPI biosynthesis in the ER. This may be an important mechanism to increase GPI when needed.

Jansen et al. introduce StableMARK (Stable Microtubule-Associated Rigor-Kinesin), a live-cell marker to visualize stable microtubules. This live-cell marker enables the exploration of different MT subsets throughout the cell cycle to understand how they contribute to cellular organization and transport.

Spatial and temporal discontinuities in time-lapse movies frequently disrupt automation methods such as 3D object segmentation and object tracking. To overcome this hurdle, we introduced SpinX, an image analysis framework to combine deep learning and mathematical object modeling to track mitotic spindle movements in 3D.

Simon et al. present ExTrack, a tool to characterize single molecules from single-particle tracking. Using a probabilistic approach, ExTrack accurately characterizes different motion states, extracts state-duration histograms, and estimates single-molecule states, even in previously intractable cases of high noise and frequent state transitions.

Gallego-Paez et al. identify a previously unannotated cassette exon in the TLN1 gene that alters the mechanical properties of the talin-1 protein. This novel exon can be readily detected in many healthy tissues including skin and pancreas, and is significantly enriched in certain cancer subtypes.