Msp1p is an intermembrane space dynamin-related protein that mediates mitochondrial fusion in a Dnm1p-dependent manner in S. pombe

FEBS Lett. 2005 Feb 14;579(5):1109-16. doi: 10.1016/j.febslet.2004.12.083. Epub 2005 Jan 18.


Mitochondrial morphology is controlled by large GTPases, such as Msp1p, whose action on mitochondrial membranes is not yet understood. The sub-mitochondrial localization of Msp1p, the subject of ongoing controversies, was found to be within the intermembrane space. Overexpression of Msp1p led to aggregation of the mitochondrial network, while its downregulation resulted in fragmentation of this network. Mutations affecting the integrity of the Msp1p GTPase function had a dominant phenotype and induced mitochondrial fragmentation followed by mitochondrial DNA loss and cell death. These effects were not observed in cells deleted for Dnm1p, an actor in mitochondrial fission, suggesting that Msp1p is involved in the fusion of mitochondria.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / chemistry
  • Adenosine Triphosphatases / genetics
  • Adenosine Triphosphatases / metabolism*
  • Amino Acid Motifs
  • DNA, Mitochondrial / metabolism
  • Dynamins / chemistry*
  • Dynamins / genetics
  • Dynamins / metabolism*
  • Fungal Proteins / chemistry
  • Fungal Proteins / genetics
  • Fungal Proteins / metabolism*
  • GTP Phosphohydrolases / chemistry
  • GTP Phosphohydrolases / metabolism
  • Gene Expression Regulation, Fungal
  • Intracellular Membranes / metabolism*
  • Mitochondria / metabolism*
  • Protein Structure, Tertiary
  • Schizosaccharomyces / cytology*
  • Schizosaccharomyces / metabolism*
  • Schizosaccharomyces pombe Proteins / chemistry
  • Schizosaccharomyces pombe Proteins / genetics
  • Schizosaccharomyces pombe Proteins / metabolism*


  • DNA, Mitochondrial
  • Fungal Proteins
  • Schizosaccharomyces pombe Proteins
  • Adenosine Triphosphatases
  • GTP Phosphohydrolases
  • Dnm1 protein, S pombe
  • Dynamins
  • Msp1 protein, S pombe