Division of mitochondria requires a novel DNM1-interacting protein, Net2p.
Mitochondria are dynamic organelles that undergo frequent division and fusion, but the molecular mechanisms of these two events are not well understood. Dnm1p, a mitochondria-associated, dynamin-related GTPase was previously shown to mediate mitochondrial fission. Recently, a genome-wide yeast two-hybrid screen identified an uncharacterized protein that interacts with Dnm1p. Cells disrupted in this new gene, which we call NET2, contain a single mitochondrion that consists of a network formed by interconnected tubules, similar to the phenotype of dnm1 Delta cells. NET2 encodes a mitochondria-associated protein with a predicted coiled-coil region and six WD-40 repeats. Immunofluorescence microscopy indicates that Net2p is located in distinct, dot-like structures along the mitochondrial surface, many of which colocalize with the Dnm1 protein. Fluorescence and immunoelectron microscopy shows that Dnm1p and Net2p preferentially colocalize at constriction sites along mitochondrial tubules. Our results suggest that Net2p is a new component of the mitochondrial division machinery.
Cerveny
K L
KL
Department of Cell Biology and Anatomy, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
McCaffery
J M
JM
Jensen
R E
RE
D000199:Actins / Q000378:metabolism / Q000648:ultrastructure; D048868:Adaptor Proteins, Signal Transducing; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D003599:Cytoskeleton / Q000235:genetics / Q000648:ultrastructure; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D020558:GTP Phosphohydrolases / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008928:Mitochondria / Q000235:genetics* / Q000378:metabolism* / Q000648:ultrastructure; D024101:Mitochondrial Proteins; D008969:Molecular Sequence Data; D009154:Mutation; D016366:Open Reading Frames; D020449:Repetitive Sequences, Amino Acid; D029701:Saccharomyces cerevisiae Proteins; D015003:Yeasts / Q000235:genetics / Q000378:metabolism*
D000199:Actins; D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; D005656:Fungal Proteins; C429283:MDV1 protein, S cerevisiae; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D029701:Saccharomyces cerevisiae Proteins; C401395:FZO1 protein, S cerevisiae; D020558:GTP Phosphohydrolases; C094774:DNM1 protein, S cerevisiae