-
Cover Image
Cover Image
On the cover
An artistically rendered image showing the spatial separation of endocytic pathways in a migrating fibroblast. Clathrin-coated vesicles (blue) are nonpolarized, while clathrin-independent carriers (red) localize to the leading edge and caveolae (green) form at the rear of the cell. Howes et al. reveal that clathrin-independent internalization is the predominant endocytic pathway in fibroblasts.
See page 675. - PDF Icon PDF LinkTable of Contents
- PDF Icon PDF LinkEditorial Board
In This Issue
In Focus
Casting the autophagy net
Two studies investigate how cells regulate the formation of autophagosomes.
People & Ideas
Martin Hetzer: Taking the nuclear membrane beyond the barrier
Hetzer investigates how the nuclear envelope and nuclear pores organize chromatin and regulate gene expression.
Review
Report
How cyclin A destruction escapes the spindle assembly checkpoint
Cyclin A outcompetes inhibitory spindle assembly checkpoint proteins for binding to the APC/C ubiquitin ligase coactivator Cdc20 to promote its self-destruction even when the checkpoint is active (see also a paper from van Zon et al., in this issue).
Autophagy requires endoplasmic reticulum targeting of the PI3-kinase complex via Atg14L
Generation of PI3P in the normally PI3P-deficient ER membrane makes the organelle a platform for autophagosome formation.
Autophagic degradation of dBruce controls DNA fragmentation in nurse cells during late Drosophila melanogaster oogenesis
Blocking autophagy protects the apoptosis inhibitor dBruce from destruction and promotes nurse cell survival in developing egg chambers.
Regulation of the autophagy protein LC3 by phosphorylation
PKA puts the brakes on autophagy by inhibiting LC3 recruitment to autophagosomes.
Identification of novel filament-forming proteins in Saccharomyces cerevisiae and Drosophila melanogaster
A screen for GFP-tagged yeast proteins that can assemble into visible structures reveals four new filamentous structures in the cytoplasm formed by metabolic enzymes and translation factors.
Coordinated RhoA signaling at the leading edge and uropod is required for T cell transendothelial migration
A biosensor for the RhoA GTPase illustrates its activation patterns in both the front and rear of migrating lymphocytes.
SNX27 mediates PDZ-directed sorting from endosomes to the plasma membrane
G protein–coupled receptors rely on the PDZ domain of SNX27 for endosomal recycling.
Article
A chromatin-bound kinase, ERK8, protects genomic integrity by inhibiting HDM2-mediated degradation of the DNA clamp PCNA
ERK8 prevents genome instability by blocking the association of the HDM2 E3 ubiquitin ligase with the genome-protecting protein PCNA.
The APC/C recruits cyclin B1–Cdk1–Cks in prometaphase before D box recognition to control mitotic exit
Prior associations with the APC/C complex during prometaphase makes cyclin B1 a better substrate for the cell cycle–regulating ubiquitin ligase in metaphase (see also a related paper by Di Fiore et al. in this issue).
Cajal body surveillance of U snRNA export complex assembly
Passage of transcribed U snRNA precursors through Cajal bodies ensures that they are properly bound to the PHAX adaptor protein required for nuclear exit.
Structure of hibernating ribosomes studied by cryoelectron tomography in vitro and in situ
CryoET shows the configuration of the ephemeral translationally inactive 100S ribosomal dimer.
Lipid activation of the signal recognition particle receptor provides spatial coordination of protein targeting
Phospholipid binding leads to accelerated assembly of the bacterial SRP receptor FtsY and SRP, allowing cargo proteins to be delivered to target membranes more efficiently.
BAG-6 is essential for selective elimination of defective proteasomal substrates
The ubiquitin-like protein BAG-6 protects cells from newly synthesized misfolded proteins by tethering them to the proteasome.
Oxidative status of muscle is determined by p107 regulation of PGC-1α
p107, a member of the retinoblastoma susceptibility protein family, influences lipid metabolism in muscle and other tissues by repressing the PPAR-γ co-factor PGC-1α.
Myosin II directly binds and inhibits Dbl family guanine nucleotide exchange factors: a possible link to Rho family GTPases
The activity of Rho GTPases in migrating cells is regulated by binding of myosin II to GEFs.
Clathrin-independent carriers form a high capacity endocytic sorting system at the leading edge of migrating cells
Quantitative ultrastructural analysis and proteomics detail CLIC structure, composition, and function.
Feedback amplification of fibrosis through matrix stiffening and COX-2 suppression
In response to tissue stiffening, fibroblasts increase production of extracellular matrix while decreasing production of matrix-degrading enzymes and the fibrosis inhibitor prostaglandin E2.
