The Plant Mitochondrial TAT Pathway Is Essential for Complex III Biogenesis.
Curr Biol
; 30(5): 840-853.e5, 2020 03 09.
Article
em En
| MEDLINE
| ID: mdl-32084398
ABSTRACT
Twin arginine translocation (TAT) pathways have been extensively studied in bacteria and chloroplasts for their role in membrane translocation of folded proteins. However, an increasing number of organisms have been found to contain mitochondria-located TAT subunits, including plant mitochondria, which contain TAT subunits, though in an unusual arrangement with only TatB and TatC subunits. To date, no confirmed function has been attributed to mitochondrial TAT pathways in any organism. Using a truncation mutant approach, we demonstrate that the plant mitochondrial TatB (MTTATB) is required for complex III biogenesis. More specifically, MTTATB performs at a late stage in complex III biogenesis, conveying the translocation of the C terminus of the Rieske FeS subunit back across the inner membrane. This work confirms that plant mitochondria retained a functional TAT pathway for the Rieske FeS translocation, most likely from the original mitochondrial ancestor. It is hypothesized that the original mitochondria contained a bacteria-derived TAT pathway required for at least the Rieske FeS translocation. In several eukaryotic lineages, this mitochondrial TAT pathway was lost and replaced by BCS1. Interestingly, plant mitochondria appear to assemble complex III in the same subunit order as yeast and mammals but in contrast use bacteria-like assembly factors for this process.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Arginina
/
Transdução de Sinais
/
Arabidopsis
/
Complexo III da Cadeia de Transporte de Elétrons
/
Transporte Proteico
/
Mitocôndrias
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article