Issues

During T cell development, genomic rearrangement must create a T cell receptor capable of transmitting signals. Allam et al. show that passage through the β-selection checkpoint requires the assembly of a platform to support TCR signaling, similar to the mature T cell immunological synapse.

Work and Brandman measure how the ubiquitin-proteasome system (UPS) adapts to different types of stressors. They find that the UPS can adapt almost perfectly to stress conditions, even those that stabilize misfolded proteins through aggregation rather than increasing UPS substrate load.

Thaller et al. demonstrate that direct binding between phosphatidic acid (PA) and the ESCRT Chm7 is required for nuclear envelope surveillance; PA also accumulates at nuclear envelope herniations. Thus, tight control of PA metabolism is required for nuclear envelope homeostasis.

Microtubule attachments to spindle poles in yeast are flexible, which allows the microtubules to pivot. Fong et al. directly measure the pivoting flexibility of the microtubule–pole interface and show that this flexibility is important for timely pole separation during mitosis.

Murillo-Pineda et al. report a chromosome engineering system for human neocentromere formation and characterize the first experimentally generated human neocentromere. Neocentromere formation promotes local H3K9me3 eviction and cohesin and RNA polymerase II recruitment. Long-term culture results in gradual maturation of the inner centromere.

Orii et al. show that phospholipids distribute symmetrically in the yeast autophagosomal membranes. They also show that de novo–synthesized phosphatidylcholine is incorporated to autophagosomal membranes preferentially and attains the symmetrical distribution within 30 min after synthesis by an Atg9-dependent manner.