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Sequence-specific Labeling of Nucleic Acids and Proteins with Methyltransferases and Cofactor Analogues
Published on: November 22, 2014
Estructura cristalina y análisis funcional de la histona metiltransferasa SET7/9/9
Jonathan R Wilson1, Chun Jing, Philip A Walker
1Structural Biology Group, National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom.
Cell
|October 10, 2002
Resumen
La metilación de la histona regula la estructura de la cromatina. Los investigadores aclararon la estructura cristalina de la SET7 / 9 humana, identificando residuos clave para la metilación de la histona H3 y la unión del cofactor con la lisina-4.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología Estructural Biología estructural.
- La epigenética es la epigenética.
Sus antecedentes:
- La metilación de la histona es crucial para regular la estructura de la cromatina.
- El dominio SET es común en las histona lisina metiltransferasas.
Objetivo del estudio:
- Para determinar la estructura cristalina de un fragmento SET7/9 humano.
- Para identificar los residuos esenciales para la metilación de histona H3 y lisina-4.
- Comprender los mecanismos de unión y catalización del cofactor (AdoMet).
Principales métodos:
- Cristalografía de rayos X de un fragmento humano SET7/9.
- Mutagénesis dirigida al sitio.
- Ensayos bioquímicos para la actividad enzimática y la interacción del sustrato.
Principales resultados:
- La estructura cristalina reveló las hojas beta N-terminal y los dominios SET.
- Se identificaron dos residuos C-terminales como esenciales para la actividad catalítica en la histona H3 lisina-4.
- Se aclaró el modo de unión del cofactor AdoMet.
- Los papeles de los residuos invariables en la catálisis, la unión de AdoMet e interacción con el sustrato fueron respaldados por datos bioquímicos.
Conclusiones:
- El estudio proporciona información estructural y bioquímica sobre la función SET7/9.
- Comprender el mecanismo SET7/9 ayuda a comprender la regulación epigenética.
- Este trabajo puede informar el desarrollo de terapias dirigidas.
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