The target of rapamycin complex 2 controls dendritic tiling of Drosophila sensory neurons through the Tricornered kinase signalling pathway

EMBO J. 2009 Dec 16;28(24):3879-92. doi: 10.1038/emboj.2009.312.

Abstract

To cover the receptive field completely and non-redundantly, neurons of certain functional groups arrange tiling of their dendrites. In Drosophila class IV dendrite arborization (da) neurons, the NDR family kinase Tricornered (Trc) is required for homotypic repulsion of dendrites that facilitates dendritic tiling. We here report that Sin1, Rictor, and target of rapamycin (TOR), components of the TOR complex 2 (TORC2), are required for dendritic tiling of class IV da neurons. Similar to trc mutants, dendrites of sin1 and rictor mutants show inappropriate overlap of the dendritic fields. TORC2 components physically and genetically interact with Trc, consistent with a shared role in regulating dendritic tiling. Moreover, TORC2 is essential for Trc phosphorylation on a residue that is critical for Trc activity in vivo and in vitro. Remarkably, neuronal expression of a dominant active form of Trc rescues the tiling defects in sin1 and rictor mutants. These findings suggest that TORC2 likely acts together with the Trc signalling pathway to regulate the dendritic tiling of class IV da neurons, and thus uncover the first neuronal function of TORC2 in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carrier Proteins / metabolism
  • Crosses, Genetic
  • Dendrites / metabolism*
  • Drosophila Proteins / metabolism*
  • Drosophila Proteins / physiology*
  • Drosophila melanogaster / metabolism*
  • HeLa Cells
  • Humans
  • Mutation
  • Neurons / metabolism*
  • Phenotype
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphatidylinositol 3-Kinases / physiology*
  • Phosphorylation
  • Protein Kinases
  • Protein Serine-Threonine Kinases / metabolism*
  • Rapamycin-Insensitive Companion of mTOR Protein
  • Sensory Receptor Cells / metabolism
  • Signal Transduction
  • TOR Serine-Threonine Kinases

Substances

  • Carrier Proteins
  • Drosophila Proteins
  • Rapamycin-Insensitive Companion of mTOR Protein
  • rictor protein, Drosophila
  • Protein Kinases
  • target of rapamycin protein, Drosophila
  • trc protein, Drosophila
  • Protein Serine-Threonine Kinases
  • TOR Serine-Threonine Kinases