SPG7 targets the m-AAA protease complex to process MCU for uniporter assembly, Ca2+ influx, and regulation of mitochondrial permeability transition pore opening.
J Biol Chem
; 294(28): 10807-10818, 2019 07 12.
Article
en En
| MEDLINE
| ID: mdl-31097542
The mitochondrial matrix ATPase associated with diverse cellular activities (m-AAA) protease spastic paraplegia 7 (SPG7) has been recently implicated as either a negative or positive regulatory component of the mitochondrial permeability transition pore (mPTP) by two research groups. To address this controversy, we investigated possible mechanisms that explain the discrepancies between these two studies. We found that loss of the SPG7 gene increased resistance to Ca2+-induced mPTP opening. However, this occurs independently of cyclophilin D (cyclosporine A insensitive) rather it is through decreased mitochondrial Ca2+ concentrations and subsequent adaptations mediated by impaired formation of functional mitochondrial Ca2+ uniporter complexes. We found that SPG7 directs the m-AAA complex to favor association with the mitochondrial Ca2+ uniporter (MCU) and MCU processing regulates higher order MCU-complex formation. The results suggest that SPG7 does not constitute a core component of the mPTP but can modulate mPTP through regulation of the basal mitochondrial Ca2+ concentration.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Metaloendopeptidasas
/
Canales de Calcio
/
ATPasas Asociadas con Actividades Celulares Diversas
Límite:
Humans
Idioma:
En
Revista:
J Biol Chem
Año:
2019
Tipo del documento:
Article
Pais de publicación:
Estados Unidos