title: Dnm1p-dependent peroxisome fission requires Caf4p, Mdv1p and Fis1p.
abstract: Yeast peroxisomes multiply by fission. Fission requires two dynamin-related proteins, Dnm1p and Vps1p. Using an in vivo fission assay, we show that Dnm1p-dependent peroxisome fission requires Fis1p, Caf4p and Mdv1p. Fluorescence microscopy of cells expressing GFP-tagged Caf4p and Mdv1p revealed that their association with peroxisomes relies on Fis1p. Vps1p-dependent peroxisome fission occurs independently of these factors. Vps1p contributes most to fission of peroxisomes when cells are grown on glucose. Overexpression of Dnm1p suppresses the fission defect as long as Fis1p and either Mdv1p or Caf4p are present. Conversely, overexpression of Dnm1p does not restore the vacuolar fusion defect of vps1 cells and Vps1p overexpression does not restore the mitochondrial fission defect of dnm1 cells. These data show that Vps1p and Dnm1p are part of independent fission machineries. Because the contribution of Dnm1p to peroxisome fission appears to be more pronounced in cells that proliferate peroxisomes in response to mitochondrial dysfunction, Dnm1p might be part of the mechanism that coordinates mitochondrial and peroxisomal biogenesis.
authors.affiliation: Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield, S10 2TN, UK.
authors.forename: Alison M
authors.initials: AM
authors.lastname: Motley
authors.forename: Gemma P
authors.initials: GP
authors.lastname: Ward
authors.forename: Ewald H
authors.initials: EH
authors.lastname: Hettema
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins / Q000378:metabolism*; D020558:GTP Phosphohydrolases / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000378:metabolism*; D020675:Peroxisomes / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D033921:Vesicular Transport Proteins
chemical_list: D048868:Adaptor Proteins, Signal Transducing; C519559:Caf4 protein, S cerevisiae; D002352:Carrier Proteins; C464859:FIS1 protein, S cerevisiae; C429283:MDV1 protein, S cerevisiae; D024101:Mitochondrial Proteins; D029701:Saccharomyces cerevisiae Proteins; D033921:Vesicular Transport Proteins; D020558:GTP Phosphohydrolases; D019204:GTP-Binding Proteins; C064553:VPS1 protein, S cerevisiae; C094774:DNM1 protein, S cerevisiae