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Las mitocondrias. las mitocondrias. Regulación dependiente del ciclo celular de la translocasa de las preproteínas

Angelika B Harbauer¹, Magdalena Opalińska², Carolin Gerbeth³

¹Institut für Biochemie und Molekularbiologie, ZBMZ, Universität Freiburg, 79104 Freiburg, Germany. Trinationales Graduiertenkolleg 1478, Universität Freiburg, 79104 Freiburg, Germany. Faculty of Biology, Universität Freiburg, 79104 Freiburg, Germany. BIOSS Centre for Biological Signalling Studies, Universität Freiburg, 79104 Freiburg, Germany.

Science (New York, N.Y.)

|November 8, 2014

Resumen

La división celular regula la función de las mitocondrias. Durante la mitosis, la fosforilación mediada por Cdk1 de Tom6 mejora la importación y el ensamblaje de proteínas mitocondriales, impulsando la actividad respiratoria.

Área de la Ciencia:

Biología celular Biología celular.
Biología mitocondrial Biología mitocondrial
Regulación del ciclo celular Reglamento del ciclo celular.

Sus antecedentes:

Las mitocondrias son cruciales para la energía celular, el metabolismo y la apoptosis.
Las mitocondrias importan más de 1000 proteínas citosólicas, pero el vínculo con la división celular no está claro.
La translocación del complejo de la membrana externa (TOM) es la puerta principal para la importación de proteínas mitocondriales.

Objetivo del estudio:

Para investigar la conexión entre el ciclo de división celular y la maquinaria de importación de proteínas mitocondriales.
Para dilucidar el mecanismo molecular por el cual la regulación del ciclo celular impacta la función mitocondrial.

Principales métodos:

Utilizó ensayos bioquímicos para estudiar la fosforilación de proteínas y el ensamblaje complejo.
Empleó técnicas de manipulación y sincronización del ciclo celular.
Evalúa la eficiencia de la importación mitocondrial y la actividad respiratoria.

Principales resultados:

La cinasa dependiente de ciclina 1 (Cdk1) estimula el ensamblaje del complejo TOM durante la mitosis.
Cdk1, activado por la ciclina Clb3, fosforila el precursor citosólico de Tom6.
El Tom6 fosforilado muestra una mayor importación en las mitocondrias, promoviendo el ensamblaje de Tom40 y la importación de otras proteínas.
Este proceso estimula la actividad respiratoria mitocondrial específicamente en la mitosis.

Conclusiones:

La importación de proteínas mitocondriales está regulada directamente por el ciclo de división celular.
La fosforilación de Tom6 por Cdk1 es un mecanismo clave que vincula la mitosis con la biogénesis y la función mitocondrial.
Esto proporciona un control específico del ciclo celular sobre la actividad mitocondrial y los niveles de energía celular.

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