Abstract
Neuronal nitric oxide synthase (nNOS) and p38MAPK are strongly implicated in excitotoxicity, a mechanism common to many neurodegenerative conditions, but the intermediary mechanism is unclear. NOS1AP is encoded by a gene recently associated with sudden cardiac death, diabetes-associated complications, and schizophrenia (Arking et al., 2006; Becker et al., 2008; Brzustowicz, 2008; Lehtinen et al., 2008). Here we find it interacts with p38MAPK-activating kinase MKK3. Excitotoxic stimulus induces recruitment of NOS1AP to nNOS in rat cortical neuron culture. Excitotoxic activation of p38MAPK and subsequent neuronal death are reduced by competing with the nNOS:NOS1AP interaction and by knockdown with NOS1AP-targeting siRNAs. We designed a cell-permeable peptide that competes for the unique PDZ domain of nNOS that interacts with NOS1AP. This peptide inhibits NMDA-induced recruitment of NOS1AP to nNOS and in vivo in rat, doubles surviving tissue in a severe model of neonatal hypoxia-ischemia, a major cause of neonatal death and pediatric disability. The highly unusual sequence specificity of the nNOS:NOS1AP interaction and involvement in excitotoxic signaling may provide future opportunities for generation of neuroprotectants with high specificity.
Publication types
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Adaptor Proteins, Signal Transducing / genetics
-
Adaptor Proteins, Signal Transducing / metabolism*
-
Analysis of Variance
-
Animals
-
Animals, Newborn
-
Brain / cytology
-
Calcium / metabolism
-
Cell Death / drug effects
-
Cell Death / physiology
-
Cells, Cultured
-
Enzyme Inhibitors / pharmacology
-
Excitatory Amino Acid Agonists / pharmacology
-
Green Fluorescent Proteins / genetics
-
Green Fluorescent Proteins / metabolism
-
Humans
-
Hypoxia / pathology
-
Intracellular Signaling Peptides and Proteins / genetics
-
Intracellular Signaling Peptides and Proteins / metabolism
-
L-Lactate Dehydrogenase / metabolism
-
N-Methylaspartate / pharmacology
-
Nerve Tissue Proteins / metabolism
-
Neurons / drug effects
-
Neurons / physiology*
-
Nitric Oxide Synthase Type I / genetics
-
Nitric Oxide Synthase Type I / metabolism*
-
Peptides / pharmacology
-
Protein Conformation
-
RNA, Small Interfering / pharmacology
-
Rats
-
Receptors, N-Methyl-D-Aspartate / metabolism
-
Signal Transduction / drug effects
-
Signal Transduction / physiology*
-
Transfection
-
p38 Mitogen-Activated Protein Kinases / metabolism*
Substances
-
Adaptor Proteins, Signal Transducing
-
Enzyme Inhibitors
-
Excitatory Amino Acid Agonists
-
Intracellular Signaling Peptides and Proteins
-
NOS1AP protein, rat
-
NR2B NMDA receptor
-
Nerve Tissue Proteins
-
Peptides
-
RNA, Small Interfering
-
Receptors, N-Methyl-D-Aspartate
-
Green Fluorescent Proteins
-
N-Methylaspartate
-
L-Lactate Dehydrogenase
-
Nitric Oxide Synthase Type I
-
p38 Mitogen-Activated Protein Kinases
-
Calcium