Protons as second messenger regulators of G protein signaling.
Mol Cell
; 51(4): 531-8, 2013 Aug 22.
Article
en En
| MEDLINE
| ID: mdl-23954348
ABSTRACT
In response to environmental stress, cells often generate pH signals that serve to protect vital cellular components and reprogram gene expression for survival. A major barrier to our understanding of this process has been the identification of signaling proteins that detect changes in intracellular pH. To identify candidate pH sensors, we developed a computer algorithm that searches proteins for networks of proton-binding sidechains. This analysis indicates that Gα subunits, the principal transducers of G protein-coupled receptor (GPCR) signals, are pH sensors. Our structure-based calculations and biophysical investigations reveal that Gα subunits contain networks of pH-sensing sidechains buried between their Ras and helical domains. Further, we show that proton binding induces changes in conformation that promote Gα phosphorylation and suppress receptor-initiated signaling. Together, our computational, biophysical, and cellular analyses reveal an unexpected function for G proteins as mediators of stress-response signaling.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Protones
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Estrés Fisiológico
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Algoritmos
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Sistemas de Mensajero Secundario
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Subunidades alfa de la Proteína de Unión al GTP
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Receptores Acoplados a Proteínas G
Límite:
Humans
Idioma:
En
Año:
2013
Tipo del documento:
Article