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Proteomics to Identify Proteins Interacting with P2X2 Ligand-Gated Cation Channels
Published on: May 18, 2009
El motivo de unión de Ca2+ bipartito en los dominios C2 de la sinaptotagmina y la proteína quinasa C
X Shao1, B A Davletov, R B Sutton
1Department of Pharmacology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75235, USA.
Science (New York, N.Y.)
|July 12, 1996
Resumen
Los investigadores identificaron un nuevo motivo de unión al calcio en los dominios C2, cruciales para las proteínas en el tráfico de la membrana y la transducción de señales. Este motivo C2 utiliza cinco residuos de aspartato para unirse a dos iones de calcio, aclarando una pregunta estructural de larga data.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología Molecular Biología Molecular
- Biología Estructural Biología estructural.
Sus antecedentes:
- Los dominios C2 son prevalentes en las proteínas que regulan el tráfico de la membrana y la transducción de señales.
- El mecanismo estructural preciso de la unión de iones de calcio a los dominios C2 sigue siendo en gran medida indefinido.
Objetivo del estudio:
- Para dilucidar la base estructural de la unión de iones de calcio en los dominios C2.
- Para identificar y caracterizar el motivo de unión al calcio dentro de proteínas específicas del dominio C2.
Principales métodos:
- Se empleó la espectroscopia de resonancia magnética nuclear (RMN) para analizar la unión del calcio.
- El estudio se centró en los dominios C2 de la sinaptotagmina I y la proteína quinasa C-beta.
Principales resultados:
- Se identificó un motivo bipartito de unión al calcio, que involucra cinco residuos de aspartato.
- Este motivo coordina la unión de dos iones de calcio a través de dos bucles distintos.
- Las comparaciones de secuencias sugieren que este motivo se conserva y se utiliza ampliamente.
Conclusiones:
- El motivo C2 representa un elemento estructural conservado para la unión del calcio en los dominios C2.
- Este hallazgo aclara el mecanismo molecular subyacente a las funciones dependientes del calcio de las proteínas del dominio C2.
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