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Un gen celular codifica la proteína PrP 27-30 de la tembladera
Cell
|April 1, 1985
Resumen
Los investigadores identificaron la principal proteína en el agente del scrapie, PrP 27-30, de cerebros de hámster infectados. Esta proteína está codificada por un solo gen en los mamíferos, y no es transportada por las partículas infecciosas de la tembladera en sí mismas.
Área de la Ciencia:
- La neurociencia es la neurociencia.
- Biología Molecular Biología Molecular
- Genética La genética.
Sus antecedentes:
- La tembladera es una encefalopatía espongiforme transmisible.
- La proteína principal en las preparaciones purificadas de agentes del scrapie es PrP 27-30.
- El origen y la base genética de PrP 27-30 no se comprendieron completamente.
Objetivo del estudio:
- Para clonar el gen que codifica PrP 27-30.
- Para investigar la base genética de PrP 27-30 en cerebros normales y infectados con scrapie.
- Para determinar si PrP 27-30 está codificado por ácidos nucleicos dentro de los priones de la tembladera.
Principales métodos:
- Las sondas de oligonucleótidos y el cribado de la biblioteca de ADNc para clonar PrP 27-30.
- Southern blotting para analizar el gen PrP.
- análisis de ARNm y Western blotting con antiserum específico.
- La digestión de la proteinasa K para diferenciar las formas de PrP.
Principales resultados:
- Se aisló un clon que codificaba PrP 27-30 del cerebro de un hámster infectado por la tembladera.
- El Southern blotting reveló un solo gen PrP en el ADN normal y infectado de hámster, ratón y humano.
- El ARNm relacionado con PrP estaba presente en niveles similares en cerebros normales e infectados y otros tejidos.
- Se detectó una proteína relacionada con PrP tanto en extractos cerebrales normales como infectados, pero solo PrP 27-30 resistió la digestión de la Proteinasa K en el cerebro infectado.
- No se encontraron ácidos nucleicos relacionados con PrP en priones purificados de la tembladera.
Conclusiones:
- PrP 27-30 está codificado por un solo gen huésped.
- El gen PrP se conserva en todas las especies de mamíferos.
- PrP 27-30 es una proteína huésped, no codificada por el ácido nucleico del agente del scrapie.
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