The helically extended SH3 domain of the T cell adaptor protein ADAP is a novel lipid interaction domain.
J Mol Biol
; 348(4): 1025-35, 2005 May 13.
Article
em En
| MEDLINE
| ID: mdl-15843031
ABSTRACT
Adhesion and degranulation-promoting adapter protein (ADAP) is critically involved in downstream signalling events triggered by the activation of the T cell receptor. Cytokine production, proliferation and integrin clustering of T cells are dependent on ADAP function, but the molecular basis for these processes is poorly understood. We now show the hSH3 domain of ADAP to be a lipid-interaction module that binds to acidic lipids, including phosphatidylinositides. Positively charged surface patches of the domain preferentially bind to polyvalent acidic lipids such as PIP2 or PIP3 over the monovalent PS phospholipid and this interaction is dependent on the N-terminal helix of the hSH3 domain fold. Basic amino acid side-chains from the SH3 scaffold also contribute to lipid binding. In the context of T cell signalling, our findings suggest that ADAP, upon recruitment to the cell-cell junction as part of a multiprotein complex, directly interacts with phosphoinositide-enriched regions of the plasma membrane. Furthermore, the ADAP lipid interaction defines the helically extended SH3 scaffold as a novel member of membrane interaction domains.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Linfócitos T
/
Domínios de Homologia de src
/
Proteínas Adaptadoras de Transdução de Sinal
/
Metabolismo dos Lipídeos
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2005
Tipo de documento:
Article