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A Method for Measuring RNA N6-methyladenosine Modifications in Cells and Tissues
Published on: December 5, 2016
La metilación de ribosa dirigida al sitio identifica grupos 2'-OH en sustratos de poliadenilación críticos para el
V J Bardwell1, M Wickens, S Bienroth
1Department of Biochemistry, College of Agriculture and Life Sciences, University of Wisconsin, Madison 53706.
Cell
|April 5, 1991
Resumen
La investigación de la poliadenilación del ARN mensajero (ARNm) reveló que los contactos específicos de azúcar dentro de la secuencia AAUAAA son cruciales para el reconocimiento por el factor de especificidad. Tanto el reconocimiento de azúcares como de bases son esenciales para esta interacción ARN-proteína.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Procesamiento de ARN Procesamiento de ARN
- La bioquímica es la bioquímica.
Sus antecedentes:
- La poliadenilación es una modificación post-transcripcional crítica de los ARN mensajeros eucariotas (ARNm).
- La secuencia de hexámero AAUAAA en la región no traducida 3' es un sitio de reconocimiento clave para la poliadenilación.
- El papel de las interacciones específicas ARN-proteína, en particular la participación de las fracciones de azúcar, en este reconocimiento no se entiende completamente.
Objetivo del estudio:
- Investigar la importancia de los contactos de azúcar para el reconocimiento específico de secuencias durante la poliadenilación de ARNm.
- Determinar la contribución de la metilación de la ribosa en posiciones específicas dentro de la secuencia AAUAAA a la eficiencia de la poliadenilación y la unión al factor.
Principales métodos:
- Sustratos de ARN sintetizados químicamente con modificaciones 2'-O-metilo (2'-O-CH3) en posiciones seleccionadas de ribosa.
- Ensayos de poliadenilación in vitro utilizando estos sustratos de ARN modificados.
- Evaluación del factor de especificidad que se une a las secuencias de ARN modificadas.
Principales resultados:
- Se produjo una poliadenilación eficiente con un sustrato de ARN metilado en todas las posiciones excepto la secuencia AAUAAA y la adenosina 3'-terminal.
- La metilación de ribosas individuales dentro de la secuencia AAUAAA inhibió significativamente tanto la adición de poli (A) como la unión al factor de especificidad.
- El grado de inhibición varió dependiendo de la posición del nucleótido de la metilación de la ribosa, lo que indica la importancia diferencial de los contactos de azúcar.
Conclusiones:
- El factor de especificidad reconoce la secuencia AAUAAA a través de contactos de ARN-proteína que involucran a las fracciones de base y azúcar.
- Los contactos específicos de ribosa en diferentes posiciones de nucleótidos dentro de AAUAAA son esenciales para una poliadenilación eficiente.
- El mecanismo de reconocimiento implica una combinación de interacciones específicas de las bases y de los azúcares, lo que pone de relieve la complejidad de la unión ARN-proteína.
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