Msp1p is an intermembrane space dynamin-related protein that mediates mitochondrial fusion in a Dnm1p-dependent manner in S. pombe.
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.
Guillou
Emmanuelle
E
Laboratoire de Biologie Cellulaire et Moléculaire du Contrôle de la Prolifération, Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 04, France.
Bousquet
Céline
C
Daloyau
Marlène
M
Emorine
Laurent J
LJ
Belenguer
Pascale
P
D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020816:Amino Acid Motifs; D004272:DNA, Mitochondrial / Q000378:metabolism; D034281:Dynamins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020558:GTP Phosphohydrolases / Q000737:chemistry / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D007425:Intracellular Membranes / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012568:Schizosaccharomyces / Q000166:cytology* / Q000378:metabolism*; D029702:Schizosaccharomyces pombe Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D004272:DNA, Mitochondrial; D005656:Fungal Proteins; D029702:Schizosaccharomyces pombe Proteins; D000251:Adenosine Triphosphatases; D020558:GTP Phosphohydrolases; C498345:Dnm1 protein, S pombe; D034281:Dynamins; C498344:Msp1 protein, S pombe