A deubiquitylating complex required for neosynthesis of a yeast mitochondrial ATP synthase subunit.
The ubiquitin system is known to be involved in maintaining the integrity of mitochondria, but little is known about the role of deubiquitylating (DUB) enzymes in such functions. Budding yeast cells deleted for UBP13 and its close homolog UBP9 displayed a high incidence of petite colonies and slow respiratory growth at 37°C. Both Ubp9 and Ubp13 interacted directly with Duf1 (DUB-associated factor 1), a WD40 motif-containing protein. Duf1 activates the DUB activity of recombinant Ubp9 and Ubp13 in vitro and deletion of DUF1 resulted in the same respiratory phenotype as the deletion of both UBP9 and UBP13. We show that the mitochondrial defects of these mutants resulted from a strong decrease at 37°C in the de novo biosynthesis of Atp9, a membrane-bound component of ATP synthase encoded by mitochondrial DNA. The defect appears at the level of ATP9 mRNA translation, while its maturation remained unchanged in the mutants. This study describes a new role of the ubiquitin system in mitochondrial biogenesis.
Institut Jacques Monod, CNRS, UMR7592, Univ Paris Diderot, Sorbonne Paris Cité, Paris, France.
Sophie
S
Kanga
Delphine
D
Bernard
Anne-Marie
AM
Mager-Heckel
Zoi
Z
Erpapazoglou
Francesca
F
Mattiroli
Titia K
TK
Sixma
Sébastien
S
Léon
Danièle
D
Urban-Grimal
Ivan
I
Tarassov
Rosine
R
Haguenauer-Tsapis
D004789:Enzyme Activation; D017353:Gene Deletion; D005838:Genotype; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism; D025261:Mitochondrial Proton-Translocating ATPases / Q000096:biosynthesis* / Q000235:genetics; D010101:Oxygen Consumption / Q000235:genetics; D011485:Protein Binding; D014176:Protein Biosynthesis / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D057149:Ubiquitinated Proteins / Q000235:genetics / Q000378:metabolism; D054875:Ubiquitination / Q000235:genetics
D029701:Saccharomyces cerevisiae Proteins; D057149:Ubiquitinated Proteins; D025261:Mitochondrial Proton-Translocating ATPases; C491522:OLI1 protein, S cerevisiae