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Glycopeptide Capture for Cell Surface Proteomics
Published on: May 9, 2014
Las epoxicetonas del péptido O-GlcNAc son reconocidas por los proteasomas de mamíferos
Martin D Witte1, Bogdan I Florea, Martijn Verdoes
1Leiden Institute of Chemistry, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands.
Journal of the American Chemical Society
|August 8, 2009
Resumen
Los proteasomas pueden reconocer proteínas modificadas con O-GlcNAc. El perfil basado en la actividad muestra que las epoxicetonas del péptido O-GlcNAc se unen a los sitios activos del proteasoma, revelando un nuevo mecanismo regulador.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología Molecular Biología Molecular
- Biología celular Biología celular.
Sus antecedentes:
- Las proteínas citosólicas y nucleares sufren modificaciones posteriores a la traducción como la O-GlcNAcilación.
- Estas proteínas también están sujetas a la degradación proteasomal.
- La interacción entre la O-GlcNAcilación y la degradación proteasómica no se entiende completamente.
Objetivo del estudio:
- Para investigar si los proteasomas reconocen los péptidos modificados O-GlcNAc.
- Proporcionar evidencia de la interacción directa entre las fracciones O-GlcNAc y los sitios catalíticos del proteasoma.
Principales métodos:
- Se empleó el perfil de proteínas basado en la actividad (ABPP).
- Se sintetizaron y utilizaron como sondas las eposiquetonas péptidas que contienen serina O-GlcNAc.
Principales resultados:
- El péptido sintetizado se une específicamente a los sitios activos catalíticos del proteasoma.
- Esta unión demuestra que los proteasomas pueden reconocer la modificación O-GlcNAc en los péptidos.
Conclusiones:
- Este estudio proporciona la primera evidencia directa de que los proteasomas reconocen péptidos que contienen la fracción O-GlcNAc.
- Este hallazgo sugiere una nueva vía reguladora que vincula la O-GlcNAcilación y la degradación de las proteínas.
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