Volume 13 Issue 1, January 2012

Volume 13 Issue 1

Research Highlights

Progress

  • Progress |

    The autophagosome, the central organelle in macroautophagy, is constructed from a membrane template called the phagophore, to which autophagy-related (ATG) proteins are hierarchically recruited. Recent findings suggest that non-canonical autophagy may also occur in the absence of these key autophagy proteins.

    • Patrice Codogno
    • , Maryam Mehrpour
    •  & Tassula Proikas-Cezanne

Reviews

  • Review Article |

    Cells use molecular motors to position and segregate organelles. Recent studies show that class V myosins function as actin-based cargo transporters in yeast, moving the vacuole, peroxisomes and secretory vesicles. There is also increasing evidence in vertebrate cells that class V myosins can serve as short-range, point-to-point organelle transporters rather than just tethering organelles to actin.

    • John A. Hammer III
    •  & James R. Sellers
  • Review Article |

    Bone homeostasis depends on the opposing activities of osteoblasts (which form bone) and osteoclasts (which destroy bone). Recent studies have revealed the transcription factors (for example, RUNX2 and osterix) and developmental signalling pathways (including WNT and Notch signalling) that regulate the differentiation and function of osteoblasts.

    • Fanxin Long
  • Review Article |

    RAS proteins are monomeric GTPases that act as binary molecular switches to regulate a wide range of cellular processes. Their trafficking and activity are regulated by constitutive post-translational modifications (PTMs), including farnesylation, methylation and palmitoylation, as well as conditional PTMs, such as phosphorylation, peptidyl-proly isomerization, ubiquitylation, nitrosylation, ADP ribosylation and glucosylation.

    • Ian M. Ahearn
    • , Kevin Haigis
    • , Dafna Bar-Sagi
    •  & Mark R. Philips

Perspectives

    Opinion

  • Opinion |

    Although the multivesicular body (MVB) is classically defined as an intermediate that delivers material for lysosomal degradation, its role in the sequestration of glycogen synthase kinase 3 during WNT signalling has revealed a positive influence of this organelle in signalling control. This Opinion article proposes that this function of MVBs as a signalling organelle is physiologically relevant during development and may be common to diverse signalling pathways.

    • Radek Dobrowolski
    •  & Edward M. De Robertis

Erratum

Corrigendum