title: Mdm31 and Mdm32 are inner membrane proteins required for maintenance of mitochondrial shape and stability of mitochondrial DNA nucleoids in yeast.
abstract: The MDM31 and MDM32 genes are required for normal distribution and morphology of mitochondria in the yeast Saccharomyces cerevisiae. They encode two related proteins located in distinct protein complexes in the mitochondrial inner membrane. Cells lacking Mdm31 and Mdm32 harbor giant spherical mitochondria with highly aberrant internal structure. Mitochondrial DNA (mtDNA) is instable in the mutants, mtDNA nucleoids are disorganized, and their association with Mmm1-containing complexes in the outer membrane is abolished. Mutant mitochondria are largely immotile, resulting in a mitochondrial inheritance defect. Deletion of either one of the MDM31 and MDM32 genes is synthetically lethal with deletion of either one of the MMM1, MMM2, MDM10, and MDM12 genes, which encode outer membrane proteins involved in mitochondrial morphogenesis and mtDNA inheritance. We propose that Mdm31 and Mdm32 cooperate with Mmm1, Mmm2, Mdm10, and Mdm12 in maintenance of mitochondrial morphology and mtDNA.
authors.affiliation: Institut für Physiologische Chemie, Universität München, 81377 München, Germany.
authors.forename: Kai Stefan
authors.initials: KS
authors.lastname: Dimmer
authors.forename: Stefan
authors.initials: S
authors.lastname: Jakobs
authors.forename: Frank
authors.initials: F
authors.lastname: Vogel
authors.forename: Katrin
authors.initials: K
authors.lastname: Altmann
authors.forename: Benedikt
authors.initials: B
authors.lastname: Westermann
mesh_terms: D000199:Actins / Q000378:metabolism; D004272:DNA, Mitochondrial / Q000378:metabolism*; D004843:Epistasis, Genetic; D042822:Genomic Instability; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007425:Intracellular Membranes / Q000378:metabolism*; D008565:Membrane Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism* / Q000648:ultrastructure; D024101:Mitochondrial Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D046912:Multiprotein Complexes; D010641:Phenotype; D010802:Phylogeny; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*
chemical_list: D000199:Actins; D004272:DNA, Mitochondrial; C497847:Mdm31 protein, S cerevisiae; C497848:Mdm32 protein, S cerevisiae; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D046912:Multiprotein Complexes; D029701:Saccharomyces cerevisiae Proteins; D049452:Green Fluorescent Proteins