Analysis of the dynein-dynactin interaction in vitro and in vivo.
Cytoplasmic dynein and dynactin are megadalton-sized multisubunit molecules that function together as a cytoskeletal motor. In the present study, we explore the mechanism of dynein-dynactin binding in vitro and then extend our findings to an in vivo context. Solution binding assays were used to define binding domains in the dynein intermediate chain (IC) and dynactin p150Glued subunit. Transient overexpression of a series of fragments of the dynein IC was used to determine the importance of this subunit for dynein function in mammalian tissue culture cells. Our results suggest that a functional dynein-dynactin interaction is required for proper microtubule organization and for the transport and localization of centrosomal components and endomembrane compartments. The dynein IC fragments have different effects on endomembrane localization, suggesting that different endomembranes may bind dynein via distinct mechanisms.
King
Stephen J
SJ
Department of Biology, The Johns Hopkins University, Baltimore, Maryland 21218, USA.
Brown
Christa L
CL
Maier
Kerstin C
KC
Quintyne
Nicholas J
NJ
Schroer
Trina A
TA
D000818:Animals; D019556:COS Cells; D002451:Cell Compartmentation / Q000502:physiology; D002522:Chlorocebus aethiops; D000072159:Dynactin Complex; D004398:Dyneins / Q000378:metabolism*; D004705:Endocytosis / Q000502:physiology; D011992:Endosomes / Q000378:metabolism; D049452:Green Fluorescent Proteins; D006367:HeLa Cells; D006801:Humans; D008164:Luminescent Proteins; D008856:Microscopy, Fluorescence; D008869:Microtubule-Associated Proteins / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism*; D011485:Protein Binding / Q000502:physiology; D017434:Protein Structure, Tertiary / Q000502:physiology; D021122:Protein Subunits / Q000378:metabolism
D000072159:Dynactin Complex; D008164:Luminescent Proteins; D008869:Microtubule-Associated Proteins; D021122:Protein Subunits; D049452:Green Fluorescent Proteins; D004398:Dyneins