The Journal of Neuroscience, January 2, 2008, 28(1):315-324; doi:10.1523/JNEUROSCI.2699-07.2008
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Development/Plasticity/Repair
p75 Neurotrophin Receptor Mediates Neuronal Cell Death by Activating GIRK Channels through Phosphatidylinositol 4,5-Bisphosphate
Elizabeth J. Coulson,1,2
Linda M. May,1
Shona L. Osborne,2
Kate Reid,1
Clare K. Underwood,1,2
Frederic A. Meunier,2
Perry F. Bartlett,1 * and
Pankaj Sah1,2 *
1Queensland Brain Institute and 2School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland 4072, Australia
Correspondence should be addressed to Elizabeth J. Coulson at the above address. Email: e.coulson{at}uq.edu.au
The pan neurotrophin receptor p75NTR signals programmed cell death both during nervous system development and after neural trauma and disease in the adult. However, the molecular pathways by which death is mediated remain poorly understood. Here, we show that this cell death is initiated by activation of G-protein-coupled inwardly rectifying potassium (GIRK/Kir3) channels and a consequent potassium efflux. Death signals stimulated by neurotrophin-mediated cleavage of p75NTR activate GIRK channels through the generation and binding of phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2/PIP2] to GIRK channels. Both GIRK channel activity and p75NTR-mediated neuronal death are inhibited by sequestration of PtdIns(4,5)P2 and application of GIRK channel inhibitors, whereas pertussis toxin treatment has no effect. Thus, p75NTR activates GIRK channels without the need for Gi/o-proteins. Our results demonstrate a novel mode of activation of GIRK channels, representing an early step in the p75NTR-mediated cell death pathway and suggesting a function for these channels during nervous system development.
Key words: nerve growth factor (NGF); regulated intramembrane proteolysis (RIP); apoptosis; Kir channel; neuronal death; phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2]; signal transduction
Received June 14, 2007;
revised Nov. 23, 2007;
accepted Nov. 27, 2007.
Correspondence should be addressed to Elizabeth J. Coulson at the above address. Email: e.coulson{at}uq.edu.au
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A. Sotthibundhu, A. M. Sykes, B. Fox, C. K. Underwood, W. Thangnipon, and E. J. Coulson
{beta}-Amyloid1-42 Induces Neuronal Death through the p75 Neurotrophin Receptor
J. Neurosci.,
April 9, 2008;
28(15):
3941 - 3946.
[Abstract]
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