September 2015 | Volume 210, No. 6
In This Issue
People & Ideas
From the Archive
- ER–mitochondrial junctions can be bypassed by dominant mutations in the endosomal protein Vps13
Substitutions in Vps13 suppress all measured phenotypic consequences of ERMES deficiency, and Vps13 dynamically localizes to vacuole–mitochondria and to vacuole–nucleus contact sites depending on growth conditions, suggesting that ERMES function can be bypassed by the activity of other contact sites, and that contact sites establish a growth condition–regulated organelle network.
- The myelin oligodendrocyte glycoprotein directly binds nerve growth factor to modulate central axon circuitry
Myelin oligodendrocyte glycoprotein, expressed on the outermost lamellae of the myelin sheath, is a novel and specific binding partner for NGF that may modulate local concentrations of the neurotrophin in the spinal cord microenvironment.
- Kinetochore function is controlled by a phospho-dependent coexpansion of inner and outer components
A subset of inner and outer kinetochore proteins responsible for lateral attachment and spindle checkpoint signaling in Xenopus egg extracts collaboratively coalesce into micrometer-scale filamentous protrusions in the absence of microtubules.
- KLP-7 acts through the Ndc80 complex to limit pole number in C. elegans oocyte meiotic spindle assembly
KLP-7/MCAK regulates kinetochore–microtubule attachment and spindle tension to promote the coalescence of early spindle pole foci, which produces a bipolar structure during the acentrosomal process of oocyte meiotic spindle assembly in C. elegans.
- Asymmetric cell division during T cell development controls downstream fate
T cell precursors undergo asymmetric cell division after T cell receptor genomic recombination, with stromal cell cues controlling the differential inheritance of fate determinants Numb and α-Adaptin by the daughters of a dividing DN3a T cell precursor.
- The fusogenic lipid phosphatidic acid promotes the biogenesis of mitochondrial outer membrane protein Ugo1
Phosphatidic acid is the first lipid required for protein-independent membrane insertion and assembly of a mitochondrial membrane protein.
- Structures of the yeast dynamin-like GTPase Sey1p provide insight into homotypic ER fusion
The crystal structures of the N-terminal cytosolic domain of Sey1p shed light on the mechanism of Sey1p-mediated ER membrane fusion.
- TRIM-mediated precision autophagy targets cytoplasmic regulators of innate immunity
TRIM20 and TRIM21 are mediators of IFN-γ–induced autophagy, which act as autophagic receptor regulators that target specific inflammasome components and type I interferon response regulators for degradation by precision autophagy.
- Prosaposin facilitates sortilin-independent lysosomal trafficking of progranulin
Prosaposin directly interacts with progranulin and facilitates progranulin lysosomal trafficking via the trafficking receptors M6PR and LRP1, independent of the previously identified progranulin trafficking pathway mediated by sortilin.
- BDNF modulates heart contraction force and long-term homeostasis through truncated TrkB.T1 receptor activation
BDNF exerts inotropic function in the adult mammalian heart through TrkB.T1 receptor and loss of this ligand/receptor system in cardiomyocytes impairs calcium signaling and causes cardiomyopathy, suggesting an essential physiological role for this pathway in cardiac function.
- α5β1 integrin recycling promotes Arp2/3-independent cancer cell invasion via the formin FHOD3
Rab-coupling protein–mediated integrin trafficking promotes filopodia formation via RhoA-ROCK-FHOD3, generating non-lamellipodial actin spike protrusions that drive cancer cell migration in 3D extracellular matrix and in vivo.