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La síntesis y la encapsidación de la transcriptasa inversa del virus de la hepatitis B del pato no requieren la
H J Schlicht1, G Radziwill, H Schaller
1Zentrum für Molekulare Biologie, Universität Heidelberg, Federal Republic of Germany.
Cell
|January 13, 1989
Resumen
La expresión del gen P del virus de la hepatitis B del pato (DHBV) comienza en la región de superposición con el gen del núcleo viral. A diferencia de los retrovirus, el producto del gen DHBV P se sintetiza a partir de su propio codón ATG, lo que permite la transcripción inversa del ARN viral.
Área de la Ciencia:
- Virología Virología.
- Biología Molecular Biología Molecular
- Investigación sobre el virus de la hepatitis B.
Sus antecedentes:
- El virus de la hepatitis B del pato (DHBV) es un hepadnavirus con un gen P que codifica la transcriptasa inversa viral.
- Comprender la estrategia de expresión del gen P es crucial para comprender la replicación viral y la patogénesis.
Objetivo del estudio:
- Para investigar la estrategia de expresión del gen P. del virus de la hepatitis B del pato (DHBV).
- Para determinar el sitio de iniciación y el mecanismo de síntesis del producto del gen P.
- Para dilucidar la complementariedad funcional y las capacidades de transcripción inversa del producto del gen P.
Principales métodos:
- Análisis mutacional del gen DHBV P.
- Evaluación de la región de iniciación de la expresión génica P.
- Evaluar la capacidad de la proteína sintetizada para complementar a los mutantes negativos para la polimerasa.
- Prueba de la transcripción inversa del ARN pregenómico viral.
Principales resultados:
- La expresión del gen DHBV P se inicia en la región que se superpone al gen del núcleo viral.
- El producto del gen P se sintetiza a partir de un codón ATG del gen P, distinto de los intermediarios de fusión gag-pol retrovirales.
- La proteína P sintetizada puede complementar a los mutantes polimerasa-negativos en trans.
- La proteína P inversa transcribe efectivamente el ARN pregenómico viral.
Conclusiones:
- El gen DHBV P utiliza una estrategia de expresión única que involucra un codón de inicio ATG dedicado.
- Este mecanismo distinto permite la síntesis de una transcriptasa viral inversa funcional.
- Los hallazgos plantean preguntas importantes con respecto a la evitación de la transcripción inversa del ARN celular en las células infectadas.
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