Interaction of mitochondria with microtubules in the filamentous fungus Neurospora crassa.
The establishment and maintenance of the 3D structure of eukaryotic cells depends on active transport and positioning of organelles along cytoskeletal elements. The biochemical basis of these processes is only poorly understood. We analysed the interaction of mitochondria with microtubules in the filamentous fungus Neurospora crassa. Mitochondria were fluorescently labelled by expression of matrix-targeted green fluorescent protein. Upon isolation, mitochondria collapsed to round spherical structures that were still able to interact with microtubules in vitro. Binding of mitochondria to microtubules was dependent on peripherally associated proteins on the organellar surface, and was sensitive to adenine nucleotides. MMM1, a mitochondrial outer membrane protein important for maintenance of normal mitochondrial morphology, was not required. This suggests that the interaction of mitochondria with the cytoskeleton is independent of MMM1. We conclude that mitochondrial morphology is maintained by a complex interplay of extrinsic and intrinsic factors, including ATP-dependent proteins on the organellar surface.
Fuchs
Florian
F
Institut für Physiologische Chemie der Universität München, Butenandtstrasse 5, D-81377 Münich, Germany.
Prokisch
Holger
H
Neupert
Walter
W
Westermann
Benedikt
B
D000255:Adenosine Triphosphate / Q000378:metabolism*; D004734:Energy Metabolism / Q000502:physiology*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal / Q000235:genetics; D005822:Genetic Vectors / Q000235:genetics; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism* / Q000648:ultrastructure; D008928:Mitochondria / Q000378:metabolism* / Q000648:ultrastructure; D009492:Neurospora crassa / Q000378:metabolism* / Q000648:ultrastructure; D010957:Plasmids / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins
D005656:Fungal Proteins; D008164:Luminescent Proteins; C089418:MMM1 protein, S cerevisiae; D008565:Membrane Proteins; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D049452:Green Fluorescent Proteins; D000255:Adenosine Triphosphate