ZFIN ID: ZDB-PUB-140310-1
The dependence receptor UNC5H2/B triggers apoptosis via PP2A-mediated dephosphorylation of DAP kinase
Guenebeaud, C., Goldschneider, D., Castets, M., Guix, C., Chazot, G., Delloye-Bourgeois, C., Eisenberg-Lerner, A., Shohat, G., Zhang, M., Laudet, V., Kimchi, A., Bernet, A., and Mehlen, P.
Date: 2010
Source: Molecular Cell   40(6): 863-876 (Journal)
Registered Authors: Laudet, Vincent
Keywords: none
MeSH Terms:
  • Apoptosis*
  • Apoptosis Regulatory Proteins/metabolism*
  • Calcium-Calmodulin-Dependent Protein Kinases/metabolism*
  • Death-Associated Protein Kinases
  • Humans
  • Phosphorylation
  • Protein Phosphatase 2/metabolism*
  • Receptors, Cell Surface/metabolism*
  • Tumor Cells, Cultured
PubMed: 21172653 Full text @ Mol. Cell

The UNC5H dependence receptors promote apoptosis in the absence of their ligand, netrin-1, and this is important for neuronal and vascular development and for limitation of cancer progression. UNC5H2 (also called UNC5B) triggers cell death through the activation of the serine-threonine protein kinase DAPk. While performing a siRNA screen to identify genes implicated in UNC5H-induced apoptosis, we identified the structural subunit PR65β of the holoenzyme protein phosphatase 2A (PP2A). We show that UNC5H2/B recruits a protein complex that includes PR65β and DAPk and retains PP2A activity. PP2A activity is required for UNC5H2/B-induced apoptosis, since it activates DAPk by triggering its dephosphorylation. Moreover, netrin-1 binding to UNC5H2/B prevents this effect through interaction of the PP2A inhibitor CIP2A to UNC5H2/B. Thus we show here that, in the absence of netrin-1, recruitment of PP2A to UNC5H2/B allows the activation of DAPk via a PP2A-mediated dephosphorylation and that this mechanism is involved in angiogenesis regulation.