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Growth-based Determination and Biochemical Confirmation of Genetic Requirements for Protein Degradation in Saccharomyces cerevisiae
Published on: February 16, 2015
Una enzima deubiquitinante interactúa con SIR4 y regula el silenciamiento en S. cerevisiae
1Department of Microbiology, University of California, San Francisco 94143, USA.
Cell
|August 23, 1996
Resumen
Las proteínas silenciadoras de la levadura SIR2, SIR3 y SIR4 interactúan con una enzima deubiquitinante, UBP3. La eliminación de UBP3 mejora el silenciamiento de genes cerca de los telómeros y los loci de tipo de apareamiento, revelando a UBP3 como un inhibidor de silenciamiento.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Genética de la levadura Genética de la levadura
- La epigenética es la epigenética.
Sus antecedentes:
- El complejo Regulador de Información Silenciosa (SIR), que comprende las proteínas SIR2, SIR3 y SIR4, es crucial para el silenciamiento transcripcional en la levadura.
- Este silenciamiento se produce en regiones genómicas específicas, incluidos los loci y los telómeros del tipo de apareamiento silencioso.
Objetivo del estudio:
- Para identificar las proteínas que se asocian con SIR4.4.
- Para investigar el papel de las proteínas de unión SIR4 en el silenciamiento transcripcional.
Principales métodos:
- Se empleó cromatografía de afinidad proteica para aislar proteínas que interactúan con SIR4.4.
- Se realizó un análisis de deleción génica para evaluar el impacto de UBP3 en el silenciamiento.
Principales resultados:
- Se encontró que SIR2, SIR3 y dos nuevas proteínas (69 y 110 kDa) se asocian estrechamente con SIR4.
- La proteína de 110 kDa fue identificada como UBP3, una enzima deubiquitinante de la levadura.
- La eliminación del gen UBP3 mejoró significativamente el silenciamiento en los telómeros y los loci del tipo de apareamiento silencioso.
Conclusiones:
- UBP3 actúa como un inhibidor del silenciamiento transcripcional en la levadura.
- UBP3 puede regular la actividad o el ensamblaje del complejo proteico SIR.
- Estos hallazgos arrojan luz sobre nuevos mecanismos reguladores que controlan el silenciamiento de genes.
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