Lipid synthesis supports membrane growth and organelle biogenesis. Hwang et al. show that synthesis of sphingolipids, mainly long-chain bases, is essential to increasing nuclear membranes during cell division. Failure to make sphingolipids in human cells causes abnormal nuclear morphology and genomic instability.

Cantwell et al. utilize Ciona and Xenopus systems to uncover conserved differential CK2 regulation of the RanGTP pathway of spindle assembly in meiosis and mitosis, contributing to the rapid, dramatic change in spindle morphology seen at the meiosis-to-mitosis transition in very early embryogenesis.

The PAX3-FOXO1 fusion gene suppresses TGFβ signaling and cell–ECM interactions by stimulating nitric oxide synthesis in fusion-positive rhabdomyosarcoma. This finding reveals that the subtype-defining molecule promotes anchorage independence and may contribute to distinct clinical behavior of rhabdomyosarcoma subtypes, suggesting subtype-specific therapies in this pediatric sarcoma.

This work reveals essential roles for TUBD1 in male germ cell development and male fertility, specifically in stabilizing the meiotic kinetochores during division and shaping the sperm head via the manchette. Our data suggest that TUBD1 interacts with katanins to achieve microtubule severing.

Narula and Wignall combine high-resolution imaging with auxin-inducible degradation to demonstrate that PLK-1 suppresses centrosome maturation and dampens microtubule polymerization in C. elegans oocytes. Since this essential kinase promotes centrosome maturation during mitosis, these findings reveal that PLK-1 plays a noncanonical role to promote the fidelity of the meiotic divisions.

Stu2 displays dynamic localization patterns in the cell cycle, with different kinetochore and microtubule distributions during distinct phases. Phosphorylation near Stu2’s C-terminus reduces its attachment to kinetochores to promote its microtubule activity in anaphase. Cdc5 and PP2A^Cdc55 play counteracting roles in this pathway to promote proper timing of Stu2 phosphorylation.

The E3 ligase Parkin ubiquitinates many proteins. Koszela et al. identify and biochemically validate a direct Parkin interaction with a substrate, Miro1. The results explain fast kinetics of Miro1 ubiquitination by Parkin in recombinant assays and provide a molecular basis for previous observations of Miro1-dependent Parkin recruitment to mitochondrial membrane.