D-amino acid oxidase activity is inhibited by an interaction with bassoon protein at the presynaptic active zone.
J Biol Chem
; 286(33): 28867-28875, 2011 Aug 19.
Article
em En
| MEDLINE
| ID: mdl-21700703
ABSTRACT
Schizophrenia is a highly heritable neuropsychiatric disorder affecting â¼1% of the world's population. Linkage and association studies have identified multiple candidate schizophrenia susceptibility genes whose functions converge on the glutamatergic neurotransmitter system. One such susceptibility gene encoding D-amino acid oxidase (DAO), an enzyme that metabolizes the NMDA receptor (NMDAR) co-agonist D-serine, has the potential to modulate NMDAR function in the context of schizophrenia. To further investigate its cellular regulation, we sought to identify DAO-interacting proteins that participate in its functional regulation in rat cerebellum, where DAO expression is especially high. Immunoprecipitation with DAO-specific antibodies and subsequent mass spectrometric analysis of co-precipitated proteins yielded 24 putative DAO-interacting proteins. The most robust interactions occurred with known components of the presynaptic active zone, such as bassoon (BSN) and piccolo (PCLO). The interaction of DAO with BSN was confirmed through co-immunoprecipitation assays using DAO- and BSN-specific antibodies. Moreover, DAO and BSN colocalized with one another in cultured cerebellar granule cells and in synaptic junction membrane protein fractions derived from rat cerebellum. The functional consequences of this interaction were studied through enzyme assay experiments, where DAO enzymatic activity was significantly inhibited as a result of its interaction with BSN. Taking these results together, we hypothesize that synaptic D-serine concentrations may be under tight regulation by a BSN-DAO complex. We therefore predict that this mechanism plays a role in the modulation of glutamatergic signaling through NMDARs. It also furthers our understanding of the biology underlying this potential therapeutic entry point for schizophrenia and other psychiatric disorders.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Serina
/
Membranas Sinápticas
/
Terminações Pré-Sinápticas
/
D-Aminoácido Oxidase
/
Proteínas do Tecido Nervoso
Limite:
Animals
/
Humans
/
Male
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article