The Journal of Neuroscience, April 8, 2009, 29(14):4420-4429; doi:10.1523/JNEUROSCI.0802-09.2009
Previous Article | Next Article 
Development/Plasticity/Repair
Synaptic Activity-Mediated Suppression of p53 and Induction of Nuclear Calcium-Regulated Neuroprotective Genes Promote Survival through Inhibition of Mitochondrial Permeability Transition
David Lau and
Hilmar Bading
Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, 69120 Heidelberg, Germany
Correspondence should be addressed to Hilmar Bading, Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany. Email: Hilmar.Bading{at}uni-hd.de
Cellular stress caused by genetic or environmental factors are considered to be the major inducers of cell death under pathological conditions. Induction of the apoptotic function of the tumor suppressor p53 is a common cellular response to severe genotoxic and oxidative stresses. In the nervous system, accumulation of p53 and increased p53 activity are associated with neuronal loss in acute and chronic neurodegenerative disorders. Here, we show that regulation of the p53 gene (trp53) is an integral part of a synaptic activity-controlled, calcium-dependent neuroprotective transcriptional program. Action potential (AP) bursting suppresses trp53 expression and downregulates key proapoptotic p53 target genes, apaf1 and bbc3 (puma). At the same time, AP bursting activates the nuclear calcium-induced neuroprotective gene, btg2. Depletion of endogenous p53 levels using RNA interference or expression of Btg2 renders neurons more resistant against excitotoxicity-induced mitochondrial permeability transitions and promotes neuronal survival under severe cellular stresses. We propose that suppression of p53 functions together with nuclear calcium-regulated neuroprotective genes in a coordinate and synergistic manner to promote neuronal survival through the stabilization of mitochondria against cellular stresses.
Received Feb. 17, 2009;
accepted March 4, 2009.
Correspondence should be addressed to Hilmar Bading, Department of Neurobiology, Interdisciplinary Center for Neurosciences, University of Heidelberg, Im Neuenheimer Feld 364, 69120 Heidelberg, Germany. Email: Hilmar.Bading{at}uni-hd.de
Related articles in J. Neurosci.:
- This Week in The Journal
J. Neurosci. 2009 29: i.
[Full Text]