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RNAi Interference by dsRNA Injection into Drosophila Embryos
Published on: April 11, 2011
La proteína hnRNP del calamar promueve el transporte citoplasmático apical y la localización de las transcripciones
S Lall1, H Francis-Lang, A Flament
1Developmental Genetics Laboratory, Imperial Cancer Research Fund, London, United Kingdom.
Cell
|July 31, 1999
Resumen
Las transcripciones genéticas de la regla de pares de Drosophila requieren proteínas nucleares para la localización apical adecuada en los embriones. El transporte citoplasmático solo es insuficiente, lo que pone de relieve el papel de las interacciones nucleo-citoplasmáticas en la regulación génica.
Área de la Ciencia:
- Biología del desarrollo Biología del desarrollo.
- Genética molecular genética molecular.
- Biología celular Biología celular.
Sus antecedentes:
- Se sabe que las transcripciones genéticas de la regla de pares en los embriones de Drosophila melanogaster se localizan apicamente de los núcleos.
- Esta localización es crucial para la segmentación y el desarrollo embrionario.
- Los mecanismos potenciales incluyen la exportación nuclear vectorial o el transporte citoplasmático.
Objetivo del estudio:
- Investigar los mecanismos subyacentes a la localización apical de las transcripciones de la regla de pares en embriones de Drosophila.
- Para determinar si los mecanismos citoplasmáticos o las interacciones nucleares son responsables de la orientación de la transcripción.
Principales métodos:
- Microinyección de transcripciones de fushi tarazu (ftz) con etiqueta fluorescente en embriones de Drosophila.
- Tratamiento de las transcripciones con extractos nucleares (Drosophila o humanos) antes de la inyección.
- Observación de patrones de localización de transcripciones usando microscopía.
- Evaluación de la dependencia de los microtúbulos para el transporte.
Principales resultados:
- Las transcripciones desnudas de ftz no pudieron localizarse apicamente, lo que indica que los mecanismos citoplasmáticos por sí solos son insuficientes.
- La preexposición a los extractos nucleares dio lugar a un transporte rápido, específico y dependiente de los microtúbulos.
- La evidencia sugiere la participación de la ribonucleoproteína nuclear heterogénea (hnRNP) del calamar (Hrp40).
- El papel de las proteínas hnRNP en la localización de transcripción se conserva evolutivamente.
Conclusiones:
- La localización de la transcripción apical en embriones de Drosophila no es únicamente un proceso citoplasmático.
- Las proteínas de pareja nuclear son esenciales para dirigir las transcripciones a sus destinos apicales.
- La maquinaria de localización citoplasmática probablemente reconoce las transcripciones en conjunción con las proteínas nucleares.
- Este mecanismo que involucra a los hnRNP se conserva en todas las especies.
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