The stoichiometry of scaffold complexes in living neurons - DLC2 functions as a dimerization engine for GKAP.
J Cell Sci
; 127(Pt 16): 3451-62, 2014 Aug 15.
Article
em En
| MEDLINE
| ID: mdl-24938595
ABSTRACT
Quantitative spatio-temporal characterization of protein interactions in living cells remains a major challenge facing modern biology. We have investigated in living neurons the spatial dependence of the stoichiometry of interactions between two core proteins of the N-methyl-D-aspartate (NMDA)-receptor-associated scaffolding complex, GKAP (also known as DLGAP1) and DLC2 (also known as DYNLL2), using a novel variation of fluorescence fluctuation microscopy called two-photon scanning number and brightness (sN&B). We found that dimerization of DLC2 was required for its interaction with GKAP, which, in turn, potentiated GKAP self-association. In the dendritic shaft, the DLC2-GKAP hetero-oligomeric complexes were composed mainly of two DLC2 and two GKAP monomers, whereas, in spines, the hetero-complexes were much larger, with an average of â¼16 DLC2 and â¼13 GKAP monomers. Disruption of the GKAP-DLC2 interaction strongly destabilized the oligomers, decreasing the spine-preferential localization of GKAP and inhibiting NMDA receptor activity. Hence, DLC2 serves a hub function in the control of glutamatergic transmission by ordering GKAP-containing complexes in dendritic spines. Beyond illuminating the role of DLC2-GKAP interactions in glutamatergic signaling, these data underscore the power of the sN&B approach for quantitative spatio-temporal imaging of other important protein complexes.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Supressoras de Tumor
/
Proteínas do Tecido Nervoso
/
Neurônios
Limite:
Animals
/
Humans
Idioma:
En
Revista:
J Cell Sci
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
França