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El transporte de H+ es una función integral del portador mitocondrial de ADP/ATP

  • 0Department of Physiology, University of California San Francisco, San Francisco, CA, USA.
Nature +

|

26 de julio de 2019

|

26 de julio de 2019

Ver abstracta en PubMed

Resumen

Este resumen es generado por máquina.

El portador mitocondrial de ADP / ATP (AAC) media tanto el intercambio de ATP / ADP como el transporte de protones. Esta doble función vincula la producción de energía y la termogénesis, controlada dinámicamente por la demanda celular de ATP.

Área De La Ciencia

  • Biología mitocondrial
  • La bioenergía
  • Transporte por membrana

Sus Antecedentes

  • El portador mitocondrial de ADP / ATP (AAC) es crucial para la producción de ATP celular mediante el intercambio de ATP mitocondrial por ADP citosólico.
  • Se ha propuesto el papel potencial de la AAC en el desacoplamiento mitocondrial, pero no está claro desde el punto de vista mecánico.

Objetivo Del Estudio

  • Para registrar directamente las corrientes AAC de las membranas mitocondriales internas del ratón.
  • Identificar y caracterizar los distintos modos de transporte de las AAC.
  • Para aclarar los mecanismos de desacoplamiento mitocondrial mediado por AAC.

Principales Métodos

  • Registro electrofisiológico directo de las corrientes AAC de las membranas mitocondriales internas aisladas.
  • Investigación del transporte de AAC en varios tejidos de ratón.
  • Análisis de la influencia de los ácidos grasos libres en la función AAC.

Principales Resultados

  • Se identificaron dos modos de transporte distintos para el AAC: el intercambio ADP/ATP y el transporte de H+.
  • La corriente de H+ mediada por AAC requiere ácidos grasos libres y se asemeja a la fuga de H+ mediada por UCP1.
  • El intercambio ADP/ATP regula negativamente, pero no elimina, la fuga de H+.

Conclusiones

  • La CAA media tanto en la conversión de energía acoplada (producción de ATP) como en la no acoplada (termogénesis).
  • Los modos de transporte duales de AAC permiten el control dinámico del desacoplamiento mitocondrial por la demanda celular de ATP.
  • AAC conecta la producción de energía celular y la generación de calor a través de sus funciones de transporte duales.

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