Neuronal remodeling and apoptosis require VCP-dependent degradation of the apoptosis inhibitor DIAP1

Development. 2011 Mar;138(6):1153-60. doi: 10.1242/dev.062703.

Abstract

The regulated degeneration of axons or dendrites (pruning) and neuronal apoptosis are widely used during development to determine the specificity of neuronal connections. Pruning and apoptosis often share similar mechanisms; for example, developmental dendrite pruning of Drosophila class IV dendritic arborization (da) neurons is induced by local caspase activation triggered by ubiquitin-mediated degradation of the caspase inhibitor DIAP1. Here, we examined the function of Valosin-containing protein (VCP), a ubiquitin-selective AAA chaperone involved in endoplasmic reticulum-associated degradation, autophagy and neurodegenerative disease, in Drosophila da neurons. Strong VCP inhibition is cell lethal, but milder inhibition interferes with dendrite pruning and developmental apoptosis. These defects are associated with impaired caspase activation and high DIAP1 levels. In cultured cells, VCP binds to DIAP1 in a ubiquitin- and BIR domain-dependent manner and facilitates its degradation. Our results establish a new link between ubiquitin, dendrite pruning and the apoptosis machinery.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / antagonists & inhibitors
  • Adenosine Triphosphatases / genetics
  • Adenosine Triphosphatases / metabolism
  • Adenosine Triphosphatases / physiology*
  • Animals
  • Animals, Genetically Modified
  • Apoptosis Regulatory Proteins / metabolism
  • Apoptosis* / genetics
  • Apoptosis* / physiology
  • Caspases / metabolism
  • Cell Cycle Proteins / antagonists & inhibitors
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism
  • Cell Cycle Proteins / physiology*
  • Cell Survival / genetics
  • Cell Survival / physiology
  • Cells, Cultured
  • Dendrites / metabolism*
  • Dendrites / physiology
  • Drosophila / genetics
  • Drosophila / metabolism
  • Drosophila / physiology
  • Drosophila Proteins / metabolism*
  • Inhibitor of Apoptosis Proteins / metabolism*
  • Models, Biological
  • Neurons / metabolism
  • Neurons / pathology
  • Neurons / physiology*
  • Protein Processing, Post-Translational / genetics
  • Stress, Physiological / genetics
  • Valosin Containing Protein

Substances

  • Apoptosis Regulatory Proteins
  • Cell Cycle Proteins
  • DIAP1 protein, Drosophila
  • Drosophila Proteins
  • Inhibitor of Apoptosis Proteins
  • Caspases
  • Adenosine Triphosphatases
  • Valosin Containing Protein