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In Vitro Ubiquitination and Deubiquitination Assays of Nucleosomal Histones
Published on: July 25, 2019
Mecanismo de la formación de la cadena de ubiquitina por el complejo humano que promueve la anafase
Lingyan Jin1, Adam Williamson, Sudeep Banerjee
1Department of Molecular and Cell Biology, 16 Barker Hall, University of California at Berkeley, Berkeley, CA 94720-3202, USA.
Cell
|May 20, 2008
Resumen
El complejo promotor de anafase (APC/C) utiliza cadenas de ubiquitina vinculadas a K11 para el control del ciclo celular. Similares motivos de caja TEK en sustratos y ubiquitina permiten un eficiente ensamblaje de la cadena y la degradación del sustrato.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
Sus antecedentes:
- El complejo promotor de la anafase (APC/C) es crucial para la progresión del ciclo celular.
- Las ligasas de ubiquitina, incluida la APC/C, unen cadenas de ubiquitina a las proteínas objetivo para la degradación.
- El mecanismo por el cual las ligasas cambian de sustrato a residuos de lisina de ubiquitina para el alargamiento de la cadena no está claro.
Objetivo del estudio:
- Para dilucidar el mecanismo de ensamblaje de la cadena de ubiquitina por el APC / C. humano.
- Determinar la topología y función de las cadenas de ubiquitina en procesos mediados por APC/C.
- Para identificar la base molecular de la especificidad en la actividad de la APC/C ubiquitina ligasa.
Principales métodos:
- Análisis estructural de la formación de la cadena de ubiquitina.
- Ensayos bioquímicos para estudiar la actividad de APC/C.
- Identificación y caracterización de los motivos clave involucrados en la ubiquitinación.
Principales resultados:
- El APC / C forma principalmente cadenas de ubiquitina vinculadas a K11 para la degradación del sustrato.
- La formación eficiente de cadenas vinculadas a K11 requiere una superficie específica en ubiquitina, denominada caja TEK.
- Los motivos homólogos de la caja TEK están presentes en los sustratos APC/C, lo que facilita la nucleación en cadena.
Conclusiones:
- El APC/C utiliza cadenas de ubiquitina vinculadas a K11 para regular la progresión del ciclo celular.
- El motivo de la caja TEK en la ubiquitina es esencial para el ensamblaje eficiente de la cadena vinculada a K11.
- El reconocimiento de motivos de caja TEK similares tanto en sustratos como en ubiquitina permite al APC/C lograr ubiquitinación específica y eficiente para el control del ciclo celular.
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