RalA and RalB relocalization to depolarized mitochondria depends on clathrin-mediated endocytosis and facilitates TBK1 activation.
PLoS One
; 14(4): e0214764, 2019.
Article
em En
| MEDLINE
| ID: mdl-30995277
ABSTRACT
Healthy mitochondria use an electrochemical gradient across the inner mitochondrial membrane (IMM) to generate energy in the form of ATP. A variety of endogenous and exogenous factors can lead to transient or sustained depolarization of the IMM, including mitochondrial fission events, expression of uncoupling proteins, electron transport chain (ETC) inhibitors, or chemical uncouplers. This depolarization in turn leads to a variety of physiological responses, ranging from selective mitochondrial clearance (mitophagy) to cell death. How cells recognize and ultimately respond to depolarized mitochondria remains incompletely understood. Here we show that the small GTPases RalA and RalB both relocalize to mitochondria following depolarization in a process dependent on clathrin-mediated endocytosis (CME). Furthermore, both genetic and pharmacologic inhibition of RalA and RalB leads to an increase in the activity of the atypical IκB kinase TBK1 both basally and in response to mitochondrial depolarization. This phenotype was also observed following inhibition of Ral relocalization. Collectively, these data suggest a model in which RalA and RalB inhibit TBK1 and that relocalization of Ral to depolarized mitochondria facilitates TBK1 activation through release of this inhibition.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Serina-Treonina Quinases
/
Proteínas ral de Ligação ao GTP
Tipo de estudo:
Prognostic_studies
Limite:
Humans
Idioma:
En
Revista:
PLoS One
Assunto da revista:
CIENCIA
/
MEDICINA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Estados Unidos