On the cover
A section through adult mouse hindlimb muscle (at the intersection of the gastrocnemius, plantaris, and soleus) shows the mutually exclusive expression of ephrin-A3 (green) and myosin heavy chain IIA (red) in slow and fast muscle fibers, respectively. Individual myofibers are outlined by laminin staining (white). Stark et al. reveal that ephrin-A3 helps slow myofibers maintain their identity by inhibiting their innervation by fast motor axons.
Image © 2015 Stark et al.
See page 1077.
- PDF Icon PDF LinkTable of Contents
- PDF Icon PDF LinkEditorial Board
In This Issue
People & Ideas
From the Archive
Microtubule-dependent long-range motility of early endosomes supports directed motility of peroxisomes, lipid droplets, and endoplasmic reticulum, and this process is mediated by transient interaction between all three organelles and the endosomes.
Yeast Pex1- and Pex6-deficient cells harbor peroxisomal membrane ghosts that lack matrix proteins but contain all major peroxisomal membrane proteins and acquire matrix proteins to develop into normal peroxisomes upon Pex1 reintroduction.
The polarity protein Inturned links NPHP4 to Daam1 to control the subapical actin network in multiciliated cells
Inturned-mediated complex formation of NPHP4 and DAAM1 is important for ciliogenesis and ciliary function in multiciliated cells, presumably because of its requirement for the local rearrangement of actin cytoskeleton.
Vitamin D receptor–retinoid X receptor heterodimer signaling regulates oligodendrocyte progenitor cell differentiation
Activation of retinoid X receptor γ and vitamin D receptor (VDR) heterodimer via vitamin D enhances oligodendrocyte progenitor differentiation, whereas blocking VDR impairs differentiation and myelination ex vivo.
An Asp–CaM complex is required for centrosome–pole cohesion and centrosome inheritance in neural stem cells
Calmodulin is required for abnormal spindle’s (Asp’s) ability to cross-link microtubules and ensure proper centrosome inheritance in neural stem cells, but it is dispensable for Asp’s role in brain size determination.
Microcephaly protein Asp focuses the minus ends of spindle microtubules at the pole and within the spindle
Asp localizes to the minus ends of spindle microtubules at the pole and within the spindle and cross-links them to adjacent microtubules.
The conserved Ski2-family helicase Obelus regulates alternative splicing of the Crumbs polarity protein to control epithelial polarity and junctional organization in Drosophila.
Reversible ubiquitination strictly controls NLRC5 function: K63-linked ubiquitination of NLRC5 at lysine 1,178 mediated by TRAF2/6 generates a coherent feedforward loop to sensitize switch-like activation of NF-κB, whereas USP14 specifically removes the polyubiquitin chains from NLRC5 to enhance NLRC5-mediated inhibition.
Analysis of Pex1 and dynamin-related protein function indicates peroxisomes multiply mainly by growth and division in Saccharomyces cerevisiae, whereas no evidence was found for the previously proposed role for Pex1 in peroxisome formation by fusion of ER-derived preperoxisomal vesicles.
A keratin scaffold regulates epidermal barrier formation, mitochondrial lipid composition, and activity
Epidermal keratin filaments are important components and organizers of the cornified envelope and regulate mitochondrial metabolism by modulating their membrane composition.
Ephrin-A3 promotes and maintains slow muscle fiber identity during postnatal development and reinnervation
During neuromuscular junction maturation and repair, ephrin-A3 is expressed by all slow (Type I) fibers and only by slow fibers, and inhibits their innervation by fast motor axons via repulsive interactions with the ephrin-A3 receptor EphA8.