Long-range transport of giant vesicles along microtubule networks.
We report on a minimal system to mimic intracellular transport of membrane-bounded, vesicular cargo. In a cell-free assay, purified kinesin-1 motor proteins were directly anchored to the membrane of giant unilamellar vesicles, and their movement studied along two-dimensional microtubule networks. Motion-tracking of vesicles with diameters of 1-3 μm revealed traveling distances up to the millimeter range. The transport velocities were identical to velocities of cargo-free motors. Using total internal reflection fluorescence (TIRF) microscopy, we were able to estimate the number of GFP-labeled motors involved in the transport of a single vesicle. We found that the vesicles were transported by the cooperative activity of typically 5-10 motor molecules. The presented assay is expected to open up further applications in the field of synthetic biology, aiming at the in vitro reconstitution of sub-cellular multi-motor transport systems. It may also find applications in bionanotechnology, where the controlled long-range transport of artificial cargo is a promising means to advance current lab-on-a-chip systems.
Biophysics, BIOTEC, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany.
Christoph
C
Herold
Cécile
C
Leduc
Robert
R
Stock
Stefan
S
Diez
Petra
P
Schwille
D032701:Biomimetics; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D016547:Kinesins / Q000235:genetics / Q000378:metabolism; D056656:Lab-On-A-Chip Devices; D008856:Microscopy, Fluorescence; D008870:Microtubules / Q000378:metabolism*; D036103:Nanotechnology; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D053835:Unilamellar Liposomes / Q000378:metabolism*
D011993:Recombinant Fusion Proteins; D053835:Unilamellar Liposomes; D049452:Green Fluorescent Proteins; D016547:Kinesins