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Estructura del genoma del virus de la leucemia murina de Abelson
Cell
|December 1, 1979
Resumen
El ARN del virus de la leucemia aviar de Moloney (A-MuLV) contiene secuencias homólogas en ambos extremos, pero una región central única. Esta región única es un insert, que reemplaza las secuencias eliminadas del virus de la leucemia murina Moloney (M-MuLV).
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Virología Virología.
- La genómica es la genómica.
Sus antecedentes:
- Los viriones del virus de la leucemia aviar de Moloney (A-MuLV) contienen un ARN de 30S, 5,6 kb.
- Este ARN se puede traducir en sistemas libres de células para producir la característica proteína A-MuLV.
Objetivo del estudio:
- Para mapear el genoma de ARN de A-MuLV.
- Para comparar el genoma A-MuLV con su supuesto progenitor, el virus de la leucemia murina de Moloney (M-MuLV).
- Para identificar secuencias homólogas y únicas dentro del genoma A-MuLV.
Principales métodos:
- Cartografía de heterodúplex utilizando las sondas de ADN de M-MuLV.
- Microscopía electrónica de heteroduplexos formados con ADN M-MuLV de longitud completa.
- Digestión de la nucleasa S1 de híbridos entre el ADN etiquetado M-MuLV y el ARN A-MuLV.
- Análisis electroforético de fragmentos digeridos para determinar longitudes de homología.
Principales resultados:
- A-MuLV y M-MuLV comparten secuencias homólogas en los extremos 5' (1320 nucleótidos) y 3' (730 nucleótidos) de sus ARN.
- La parte central del genoma A-MuLV no es homólogo al ARN M-MuLV.
- Aproximadamente 6200 nucleótidos del ARN M-MuLV fueron eliminados y reemplazados por un insert de 3600 nucleótidos en el genoma A-MuLV.
Conclusiones:
- El genoma A-MuLV es una molécula recombinante derivada de M-MuLV.
- La región central única del ARN A-MuLV probablemente se deriva del genoma murino normal.
- Esta estructura genómica explica las distintas propiedades de A-MuLV en comparación con M-MuLV.
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