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La dinámica del ARNm materno poli (A) contenido en huevos de erizo de mar fertilizados

|July 1, 1977

Resumen

La activación del huevo de erizo de mar duplica la cantidad de ARN poli (A) sin cambiar el ARN total. Este aumento en el ARN poliadenilado implica más secuencias y más largos tractos poli (A), no nuevas secuencias de ARN.

Área de la Ciencia:

Biología Molecular Biología Molecular
Biología del desarrollo Biología del desarrollo.
ARN Biología Biología ARN

Sus antecedentes:

Los huevos de erizo de mar no fertilizados contienen ARN poliadenilado secuestrado (ARN poli (A) + ARN).
La activación del huevo desencadena cambios significativos en el metabolismo del ARN.

Objetivo del estudio:

Para investigar los cambios en el ARN poli (A) durante el desarrollo temprano del erizo de mar.
Para determinar si las nuevas secuencias de ARN son poliadeniladas después de la fertilización.

Principales métodos:

Cromatografía poli (U) -sefarosa para cuantificar el ARN poli (A) +.
cinética de hibridación de ADNc para comparar secuencias de ARN en huevos y cigotos.
Medición de la longitud del tracto polio (A) utilizando las relaciones adenosina/AMP.

Principales resultados:

La cantidad de ARN poli (A) se duplica después de la fecundación, mientras que el ARN total permanece constante.
El número de secuencias poliadeniladas y la longitud de los tractos poli (A) aumentan.
Las secuencias de ARN que llevan poli (A) son idénticas en huevos y cigotos, lo que indica que no hay una nueva secuencia de poliadenilación.
La longitud del tracto de poli (A) aumenta de aproximadamente 45 a 60 bases, con evidencia de rotación de poli (A).

Conclusiones:

La dinámica del ARN poli (A) en zigotos de erizo de mar implica tanto el alargamiento como el acortamiento de los tractos poli (A), con un alargamiento neto observado.
El aumento en el poli (A) se atribuye a un mayor número de secuencias poliadeniladas y el alargamiento de los tractos poli (A) existentes, no a la adición de nuevas secuencias de ARN.

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