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El poro de transición de permeabilidad mitocondrial: pasado, presente y futuro

Michela Carraro¹, Christoph Gerle², Paolo Bernardi¹

¹1Department of Biomedical Sciences, University of Padova, Padova, Italy; email: paolo.bernardi@unipd.it, michela.carraro@unipd.it.

Annual review of biophysics

|December 12, 2025

Resumen

La transición de permeabilidad mitocondrial (PT) implica un canal en la membrana mitocondrial interna. La investigación sugiere que la ATP sintasa forma estos canales, pero no en todas las especies, lo que afecta la susceptibilidad a la PT.

Área de la Ciencia:

Fisiología y bioenergética mitocondrial
Biología molecular de canales iónicos
Bioquímica comparada

Sus antecedentes:

La transición de permeabilidad (PT) mitocondrial es un evento crítico que implica una mayor permeabilidad de la membrana mitocondrial interna.
Este proceso está mediado por la apertura del poro de transición de permeabilidad (PTP), un canal de alta conductancia.
Si bien la identidad molecular del PTP ha sido objeto de debate, el consenso apunta a conformaciones específicas de la ATP sintasa F_OF₁ y el translocador de nucleótidos de adenina.

Objetivo del estudio:

Investigar el papel de la ATP sintasa en la formación de canales relacionados con la transición de permeabilidad mitocondrial.
Comparar las propiedades de formación de canales de las ATP sintasas en diferentes especies con susceptibilidad variable a la PT.
Proporcionar un marco estructural para comprender el mecanismo de formación de canales o su ausencia.

Principales métodos:

Análisis comparativo de las estructuras de ATP sintasa de diversas especies.
Revisión de la literatura existente sobre la transición de permeabilidad mitocondrial y la formación de canales.
Inferencia a partir de datos estructurales para hipotetizar sobre los mecanismos de los canales.

Principales resultados:

La ATP sintasa forma canales de alta conductancia en mamíferos y levaduras, asociados con la PT.
La ATP sintasa en *Artemia franciscana* no forma canales de alta conductancia y es refractaria a la PT.
La ATP sintasa en *Drosophila melanogaster* forma canales de baja conductancia y selectivos para Ca2+, lo que conduce a la liberación de Ca2+ inducida por Ca2+ pero no a la PT.

Conclusiones:

La capacidad de formación de canales de la ATP sintasa varía significativamente entre especies.
Las diferencias estructurales específicas de la especie en la ATP sintasa probablemente determinan su susceptibilidad a la transición de permeabilidad mitocondrial.
Las ideas estructurales sobre las ATP sintasas ofrecen un modelo comprobable para la investigación futura sobre los mecanismos del PTP.

Palabras clave:

transición de permeabilidad mitocondrial ATP sintasa poro de transición de permeabilidad fisiología mitocondrial bioenergética biología molecular canales iónicos bioquímica comparada

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