Volume 10 Issue 8, August 2009

From The Editors

Research Highlights

Progress

  • Progress |

    The Bicoid (BCD) morphogen gradient was thought to be formed by diffusion of the protein away from the anterior pole of the Drosophila melanogaster embryo. A new study shows that a bcd mRNA gradient prefigures the protein gradient and proposes a model that combines active mRNA transport with local BCD translation.

    • Howard D. Lipshitz

Reviews

  • Review Article |

    Rab GTPases control intracellular vesicle traffic by acting as regulatable switches that recruit effector molecules when in their GTP-bound form. The functional coupling between multiple Rab GTPases ensures the spatiotemporally coordinated regulation of vesicle traffic.

    • Harald Stenmark
  • Review Article |

    The life cycle of an organism is characterized by phases of reprogramming and differentiation during development from the zygote to the adult organism. Lineage-determining transcription factors and epigenetic mechanisms form inseparable strands that regulate pluripotency and early cell lineage decisions.

    • Myriam Hemberger
    • , Wendy Dean
    •  & Wolf Reik
  • Review Article |

    Directional cell migration is achieved by forming and stabilizing protrusions or lamellipodia at the leading edge of the cell. Many factors and processes can affect leading edge formation, and they often depend on local regulation of the Rho family of GTPases.

    • Ryan J. Petrie
    • , Andrew D. Doyle
    •  & Kenneth M. Yamada
  • Review Article |

    A large superfamily of deubiquitinases (DUBs) has a key role in both determining protein stability and terminating ubiquitin-dependent signal transduction. Structural and biochemical studies have started to reveal the underlying principles by which DUB substrate specificity is achieved.

    • David Komander
    • , Michael J. Clague
    •  & Sylvie Urbé

Perspectives

    Opinions

  • Opinion |

    Protein sumoylation affects many biological processes, but it was not previously thought to target proteins for degradation. Recent findings unravel a new role for small ubiquitin-like modifier (SUMO) as a signal for the recruitment of ubiquitin ligases, which leads to protein ubiquitylation and degradation.

    • Marie-Claude Geoffroy
    •  & Ronald T. Hay
  • Opinion |

    The growth of microtubules is accompanied by large fluctuations in rates and abrupt transitions between phases of growth and shrinkage. The authors propose that fluctuations in the length of the GTP–tubulin cap at the microtubule end could be the main source of variation.

    • Jonathon Howard
    •  & Anthony A. Hyman