A nonproteolytic proteasome activity controls organelle fission in yeast.
To understand the processes underlying organelle function, dynamics and inheritance, it is necessary to identify and characterize the regulatory components involved. Recently in yeast and mammals, proteins of the membrane fission machinery (Dnm1-Mdv1-Caf4-Fis1 in yeast and DLP1-FIS1 in human) have been shown to have a dual localization on mitochondria and peroxisomes, where they control mitochondrial fission and peroxisome division. Here, we show that whereas vacuole fusion is regulated by the proteasome degradation function, mitochondrial fission and peroxisomal division are not controlled by the proteasome activity but rather depend on a new function of the proteasomal lid subunit Rpn11. Rpn11 was found to regulate the Fis1-dependent fission machinery of both organelles. These findings indicate a unique role of the Rpn11 protein in mitochondrial fission and peroxisomal proliferation that is independent of its role in proteasome-associated deubiquitylation.
Hofmann
Line
L
University of Paris-Sud, CNRS, UMR 8621, Institute of Genetics and Microbiology, Orsay 91405, France.
Saunier
Rémy
R
Cossard
Raynald
R
Esposito
Michela
M
Rinaldi
Teresa
T
Delahodde
Agnès
A
D000595:Amino Acid Sequence; D020134:Catalytic Domain; D002453:Cell Cycle / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D005947:Glucose / Q000494:pharmacology; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D019301:Oleic Acid / Q000494:pharmacology; D015388:Organelles / Q000187:drug effects / Q000378:metabolism*; D020675:Peroxisomes / Q000187:drug effects / Q000378:metabolism; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D011499:Protein Processing, Post-Translational / Q000187:drug effects; D055550:Protein Stability / Q000187:drug effects; D021381:Protein Transport / Q000187:drug effects; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism; D013696:Temperature
D029701:Saccharomyces cerevisiae Proteins; D019301:Oleic Acid; D046988:Proteasome Endopeptidase Complex; D005947:Glucose