Mdm31 and Mdm32 are inner membrane proteins required for maintenance of mitochondrial shape and stability of mitochondrial DNA nucleoids in yeast

Kai Stefan Dimmer; Stefan Jakobs; Frank Vogel; Katrin Altmann; Benedikt Westermann

doi:10.1083/jcb.200410030

Mdm31 and Mdm32 are inner membrane proteins required for maintenance of mitochondrial shape and stability of mitochondrial DNA nucleoids in yeast

J Cell Biol. 2005 Jan 3;168(1):103-15. doi: 10.1083/jcb.200410030.

Authors

Kai Stefan Dimmer¹, Stefan Jakobs, Frank Vogel, Katrin Altmann, Benedikt Westermann

Affiliation

¹ Institut für Physiologische Chemie, Universität München, 81377 München, Germany.

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.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Actins / metabolism
DNA, Mitochondrial / metabolism*
Epistasis, Genetic
Genomic Instability
Green Fluorescent Proteins / genetics
Green Fluorescent Proteins / metabolism
Humans
Intracellular Membranes / metabolism*
Membrane Proteins / classification
Membrane Proteins / genetics
Membrane Proteins / metabolism*
Mitochondria / metabolism*
Mitochondria / ultrastructure
Mitochondrial Proteins / classification
Mitochondrial Proteins / genetics
Mitochondrial Proteins / metabolism*
Multiprotein Complexes
Phenotype
Phylogeny
Saccharomyces cerevisiae / cytology
Saccharomyces cerevisiae / metabolism
Saccharomyces cerevisiae Proteins / classification
Saccharomyces cerevisiae Proteins / genetics
Saccharomyces cerevisiae Proteins / metabolism*

Substances

Actins
DNA, Mitochondrial
Mdm31 protein, S cerevisiae
Mdm32 protein, S cerevisiae
Membrane Proteins
Mitochondrial Proteins
Multiprotein Complexes
Saccharomyces cerevisiae Proteins
Green Fluorescent Proteins