Volume 12 Issue 2, February 2010

Volume 12 Issue 2

Transplantation of GFP-positive muscle-derived adipogenic progenitors (green) induces ectopic fat deposit and activates myogenesis.p153

Editorial

  • Editorial |

    Mentoring enhances the experience of mentees; however, mentors and their institutions will also reap the rewards of a mentorship culture.

News and Views

  • News & Views |

    Adipocytes and scar tissue form during skeletal muscle degeneration. Two new studies reveal that adipocytes and fibroblasts in skeletal muscle derive from a population of bipotent progenitors that reside within muscle, but are not derived from the muscle lineage. These progenitor cells also have a surprising role in stimulating the restoration of muscle mass during regeneration.

    • Matthew S. Rodeheffer
  • News & Views |

    Recent studies have revealed a prominent role of mitochondrial dysfunction in the development of one of the most common neurodegenerative disorders, Parkinson's disease. The ubiquitin ligase Parkin and the protein kinase PINK1, whose mutations are associated with Parkinson's disease, function in a pathway that links ubiquitylation with selective autophagy of damaged mitochondria.

    • Philipp Wild
    •  & Ivan Dikic
  • News & Views |

    Separation of sister chromatids at anaphase in metazoan cells requires only the cleavage of the kleisin subunit of centromeric cohesin, but efficient poleward movement of separated sisters requires the associated loss in Cdk1 activity. Activation of the anaphase-promoting complex/cyclosome ensures these events are coordinated.

    • Keith T. Jones

Research Highlights

Articles

  • Article |

    In budding yeast, many inducible genes translocate to the nuclear periphery when activated. Sequence motifs have now been identified in promoters, which target genes to the nuclear periphery and contribute to gene activation

    • Sara Ahmed
    • , Donna G. Brickner
    • , William H. Light
    • , Ivelisse Cajigas
    • , Michele McDonough
    • , Alexander B. Froyshteter
    • , Tom Volpe
    •  & Jason H. Brickner
  • Article |

    The E3 ubiquitin ligase Parkin mediates the clearance of depolarized mitochondria through the autophagy pathway. PINK1 kinase activity is required for Parkin translocation to depolarized mitochondria where Parkin generates polyubiquitin chains on the voltage-dependent anion channel (VDAC1) to recruit the autophagic adaptor p62/SQSTM1.

    • Sven Geisler
    • , Kira M. Holmström
    • , Diana Skujat
    • , Fabienne C. Fiesel
    • , Oliver C. Rothfuss
    • , Philipp J. Kahle
    •  & Wolfdieter Springer
  • Article |

    Hedgehog signalling and activation of its downstream effectors Gli1/2 is deregulated in tumorigenesis. Hedgehog-induced HDAC1 is shown to activate Gli1/2 through its deacetylation. This effect is negatively regulated by the Cullin3/RENKCTD11 ubiquitin ligase, a Gli antagonist that is often lost in human medulloblastoma.

    • Gianluca Canettieri
    • , Lucia Di Marcotullio
    • , Azzura Greco
    • , Sonia Coni
    • , Laura Antonucci
    • , Paola Infante
    • , Laura Pietrosanti
    • , Enrico De Smaele
    • , Elisabetta Ferretti
    • , Evelina Miele
    • , Marianna Pelloni
    • , Giuseppina De Simone
    • , Emilia Maria Pedone
    • , Paola Gallinari
    • , Alessandra Giorgi
    • , Christian Steinkühler
    • , Luigi Vitagliano
    • , Carlo Pedone
    • , M. Eugenià Schinin
    • , Isabella Screpanti
    •  & Alberto Gulino
  • Article |

    Following skeletal muscle damage, a population of resident fibro/adipogenic progenitors (FAP) initiates proliferation, resulting in the generation of ectopic white fat but not myofibres. FAPs enhance the differentiation of the myogenic progenitors involved in muscle regeneration.

    • Aaron W. B. Joe
    • , Lin Yi
    • , Anuradha Natarajan
    • , Fabien Le Grand
    • , Leslie So
    • , Joy Wang
    • , Michael A. Rudnicki
    •  & Fabio M. V. Rossi

Letters

  • Letter |

    Mouse node cilia are posteriorly tilted to generate a leftward fluid flow and left/right asymmetry in the embryo, but how the tilt comes about was not known. The basal bodies of node cilia gradually shift from a central position towards the posterior side of node cells in a dishevelled and non-canonical Wnt signalling-dependent manner and follow a shift in Dvl localization to the posterior.

    • Masakazu Hashimoto
    • , Kyosuke Shinohara
    • , Jianbo Wang
    • , Shingo Ikeuchi
    • , Satoko Yoshiba
    • , Chikara Meno
    • , Shigenori Nonaka
    • , Shinji Takada
    • , Kohei Hatta
    • , Anthony Wynshaw-Boris
    •  & Hiroshi Hamada
  • Letter |

    The ATM signalling mediator proteins 53BP1 and KAP-1 are required for heterochromatic double-strand break DNA repair. 53BP1 aids Mre11, NBS1 and ATM accumulation at heterochromatic breaks, leading to localized phosphorylation of KAP-1 by ATM.

    • Angela T. Noon
    • , Atsushi Shibata
    • , Nicole Rief
    • , Markus Löbrich
    • , Grant S. Stewart
    • , Penelope A. Jeggo
    •  & Aaron A. Goodarzi
  • Letter |

    Whether cohesion-independent forces hold chromosomes together in metaphase is a debated issue. Artificial cleavage of cohesin is sufficient to induce chromosome disjunction in Drosophila syncytical embryos but cdk1 inactivation is required for normal subsequent chromosome separation.

    • Raquel A. Oliveira
    • , Russell S. Hamilton
    • , Andrea Pauli
    • , Ilan Davis
    •  & Kim Nasmyth
  • Letter |

    The role of Kaposi's sarcoma-associated herpesvirus microRNAs in viral infection and replication remains unclear. A viral cluster containing 14 microRNAs is shown to negatively regulate viral replication by targeting the the NF-κB inhibitor IκBα and thereby decreasing NF-κB signalling.

    • Xiufen Lei
    • , Zhiqiang Bai
    • , Fengchun Ye
    • , Jianping Xie
    • , Chan-Gil Kim
    • , Yufei Huang
    •  & Shou-Jiang Gao

Corrigendum