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La traducción dependiente del crecimiento del ARNm IGF-II por una vía sensible a la rapamicina
F C Nielsen1, L Ostergaard, J Nielsen
1Department of Clinical Biochemistry, Rigshospitalet, Copenhagen O, Denmark.
Nature
|September 28, 1995
Resumen
El gen IGF-II humano produce dos tipos principales de ARNm. Un ARNm menor produce continuamente prepro-IGF-II, mientras que un ARNm mayor es regulado por una vía específica de la quinasa.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Biología celular Biología celular.
- Genética La genética.
Sus antecedentes:
- El factor de crecimiento similar a la insulina (IGF) -II es crucial para el crecimiento fetal.
- El gen IGF-II humano produce múltiples transcripciones de ARNm con diferentes regiones 5' no traducidas (5'UTR).
- Anteriormente, se identificó un ARNm de 4.8 kb para la síntesis de pre-pro-IGF-II, y se encontró que un ARNm de 6.0 kb no se tradujo y se almacenó en 100S partículas de ribonucleoproteína.
Objetivo del estudio:
- Para investigar la regulación de la traducción del ARNm IGF-II de 6,0 kilobytes.
- Aclarar la vía de señalización involucrada en la movilización y traducción del ARNm IGF-II de 6,0 kilobytes.
Principales métodos:
- Cultivo celular de células dispersas de crecimiento exponencial.
- Tratamiento con rapamicina y anisomicina para estudiar la regulación traslacional.
- Análisis de la movilización y traducción del ARNm.
Principales resultados:
- El ARNm IGF-II de 6.0 kilobytes se moviliza selectivamente y se traduce en células de crecimiento exponencial.
- La rapamicina inhibe, mientras que la anisomicina imita, la traducción del ARNm de 6.0 kilobytes.
- Esto sugiere una regulación por la vía de señalización de la quinasa p70S6k/85S6k.
Conclusiones:
- El ARNm de IGF-II de 4.8kb asegura la producción constitutiva del IGF-II prepro.
- El ARNm IGF-II de 6.0 kilobytes representa una especie regulada post-transcripcionalmente. el ARNm IGF-II de 6.0 kilobytes representa una especie regulada post-transcripcionalmente. el ARNm IGF-II de 6.0 kilobytes representa una especie regulada post-transcripcionalmente. el ARNm IGF-II de 6.0 kilobytes representa una especie regulada post-transcripcionalmente. el ARNm IGF-II de 6.0 kilobytes representa una especie regulada post-transcripcionalmente. el ARNm IGF-II de 6.0 kilobytes representa una especie regulada post-transcripcionalmente.
- La vía p70S6k/85S6k controla la traducción de la transcripción del ARNm principal IGF-II.
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