Slow phosphorylation of a tyrosine residue in LAT optimizes T cell ligand discrimination.
Nat Immunol
; 20(11): 1481-1493, 2019 11.
Article
en En
| MEDLINE
| ID: mdl-31611699
ABSTRACT
Self-non-self discrimination is central to T cell-mediated immunity. The kinetic proofreading model can explain T cell antigen receptor (TCR) ligand discrimination; however, the rate-limiting steps have not been identified. Here, we show that tyrosine phosphorylation of the T cell adapter protein LAT at position Y132 is a critical kinetic bottleneck for ligand discrimination. LAT phosphorylation at Y132, mediated by the kinase ZAP-70, leads to the recruitment and activation of phospholipase C-γ1 (PLC-γ1), an important effector molecule for T cell activation. The slow phosphorylation of Y132, relative to other phosphosites on LAT, is governed by a preceding glycine residue (G131) but can be accelerated by substituting this glycine with aspartate or glutamate. Acceleration of Y132 phosphorylation increases the speed and magnitude of PLC-γ1 activation and enhances T cell sensitivity to weaker stimuli, including weak agonists and self-peptides. These observations suggest that the slow phosphorylation of Y132 acts as a proofreading step to facilitate T cell ligand discrimination.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Activación de Linfocitos
/
Receptores de Antígenos de Linfocitos T
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Linfocitos T
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Proteínas Adaptadoras Transductoras de Señales
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Proteínas de la Membrana
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
Nat Immunol
Asunto de la revista:
ALERGIA E IMUNOLOGIA
Año:
2019
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
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US
/
USA