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Inactivación traslacional de la función de ARN: discriminación contra un subconjunto de transcripciones genómicas
M Nassal1, M Junker-Niepmann, H Schaller
1Zentrum für Molekulare Biologie, Universität Heidelberg, Germany.
Cell
|December 21, 1990
Resumen
El ensamblaje del virus de la hepatitis B (VHB) es selectivo. La traducción de los ribosomas bloquea las señales de encapsidación en algunos ARN virales, asegurando que solo se empaqueten los pregenomas funcionales. Esto revela un nuevo mecanismo de regulación del ARN.
Área de la Ciencia:
- Virología Virología.
- Biología Molecular Biología Molecular
- Genética La genética.
Sus antecedentes:
- El virus de la hepatitis B (VHB) es un virus de ADN que se replica a través de la transcripción inversa.
- El ensamblaje de los nucleocápsidos del VHB requiere interacciones específicas entre las proteínas del núcleo, los productos del gen P y el ARN del pregenoma.
- Una señal de encapsidación de acción cis marca el pregenoma para el envasado.
Objetivo del estudio:
- Para dilucidar el mecanismo de la encapsidación selectiva del ARN del VHB.
- Para entender por qué algunas transcripciones del VHB con señales de encapsidación no están empaquetadas.
Principales métodos:
- Investigó el papel de la traducción de los ribosomas en la selección del ARN del VHB.
- Diferenciado entre el escaneo de subunidades ribosómicas 40S y la traducción de ribosomas 80S.
Principales resultados:
- La traducción de los ribosomas 80S que avanzan hacia la señal de encapsidación inhibe su función.
- La exploración de las subunidades ribosómicas 40S no impide la función de la señal.
- Este control traslacional explica el empaquetado selectivo del ARN del VHB.
Conclusiones:
- El VHB utiliza la modulación traslacional de la función del ARN para la regulación del genoma.
- Este mecanismo permite un uso eficiente del genoma compacto del VHB.
- La actividad de los ribosomas es un factor clave en el control de la replicación del VHB.
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