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Mapping the Binding Site of an Aptamer on ATP Using MicroScale Thermophoresis
Published on: January 7, 2017
La actividad sináptica en los receptores AMPA permeables al calcio induce un cambio en el subtipo del receptor
1Department of Pharmacology, University College London, UK.
Nature
|June 6, 2000
Resumen
La actividad sináptica altera rápidamente la composición del receptor del ácido propiónico alfa-amino-3-hidroxi-5-metil-4-isoxazol (AMPAR) en las células esteladas cerebelares. Este cambio modifica la transmisión sináptica mediante la incorporación de AMPARs que contienen GluR2, que regulan la permeabilidad del calcio.
Área de la Ciencia:
- La neurociencia es la neurociencia.
- La plasticidad sináptica.
- Biología Molecular Biología Molecular
Sus antecedentes:
- La plasticidad sináptica dependiente de la actividad es crucial para la función del sistema nervioso central.
- Las modificaciones postsinápticas a menudo implican cambios en la capacidad de respuesta del receptor de ácido propiónico alfa-amino-3-hidroxi-5-metil-4-isoxazol (AMPAR).
- Los modelos existentes sugieren que las alteraciones en el número de AMPAR y el estado de fosforilación impulsan estos cambios.
Objetivo del estudio:
- Investigar una nueva forma de plasticidad sináptica que involucra la composición de las subunidades de AMPAR y la permeabilidad de Ca2+.
- Para aclarar el papel de la subunidad GluR2 en las modificaciones sinápticas dependientes de la actividad en las sinapsis de células estelares cerebelares.
Principales métodos:
- Utilizó técnicas electrofisiológicas para monitorear las corrientes sinápticas.
- Investigó la permeabilidad de Ca2+ y el bloqueo de poliamina de los AMPAR.
- Rastreó la incorporación de AMPARs que contienen GluR2 después de la estimulación sináptica.
Principales resultados:
- Se identificó un cambio rápido y duradero en la composición de las subunidades de AMPAR y la permeabilidad de Ca2+ en las sinapsis de células estelares cerebelares.
- Se ha demostrado que la activación sináptica repetitiva de los AMPAR Ca2+ permeables conduce a una reducción de la permeabilidad de Ca2+.
- Se demostró que la afluencia de Ca2+ inducida por la actividad a través de los AMPAR que carecen de GluR2 regula la orientación de los AMPAR que contienen GluR2.
Conclusiones:
- El influjo de Ca2+ dependiente de la actividad a través de los AMPAR que carecen de GluR2 controla la incorporación de los AMPAR que contienen GluR2.
- Este proceso representa un mecanismo de autorregulación para la eficacia de la transmisión sináptica.
- Destaca una nueva forma de plasticidad sináptica mediada por cambios en la composición de las subunidades de AMPAR.
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