Abstract
The active forward movement of cells is often associated with the rearward transport of particles over the surfaces of their lamellae. Unlike the rest of the lamella, we found that the leading edge (within 0.5 microns of the cell boundary) is specialized for rearward transport of membrane-bound particles, such as Con A-coated latex microspheres. Using a single-beam optical gradient trap (optical tweezers) to apply restraining forces to particles, we can capture, move and release particles at will. When first bound on the central lamellar surface, Con A-coated particles would diffuse randomly; when such bound particles were brought to the leading edge of the lamella with the optical tweezers, they were often transported rearward. As in our previous studies, particle transport occurred with a concurrent decrease in apparent diffusion coefficient, consistent with attachment to the cytoskeleton. For particles at the leading edge of the lamella, weak attachment to the cytoskeleton and transport occurred with a half-time of 3 s; equivalent particles elsewhere on the lamella showed no detectable attachment when monitored for several minutes. Particles held on the cell surface by the laser trap attached more strongly to the cytoskeleton with time. These particles could escape a trapping force of 0.7 × 10-6 dyne after 18 ± 14 (sd) s at the leading edge, and after 64 ± 34 (SD) s elsewhere on the lamella. Fluorescent succinylated Con A staining showed no corresponding concentration of general glycoproteins at the leading edge, but cytochalasin D-resistant filamentous actin was found at the leading edge. Our results have implications for cell motility: if the forces used for rearward particle transport were applied to a rigid substratum, cells would move forward. Such a mechanism would be most efficient if the leading edge of the cell contained preferential sites for attachment and transport.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1029-1036 |
| Number of pages | 8 |
| Journal | Journal of Cell Biology |
| Volume | 114 |
| Issue number | 5 |
| DOIs | |
| State | Published - Jan 1 1991 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Cell Biology
Cite this
Preferential attachment of membrane glycoproteins to the cytoskeleton at the leading edge of lamella. / Kucik, Dennis F.; Kuo, Scot C.; Elson, Elliot L.; Sheetz, Michael.
In: Journal of Cell Biology, Vol. 114, No. 5, 01.01.1991, p. 1029-1036.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Preferential attachment of membrane glycoproteins to the cytoskeleton at the leading edge of lamella
AU - Kucik, Dennis F.
AU - Kuo, Scot C.
AU - Elson, Elliot L.
AU - Sheetz, Michael
PY - 1991/1/1
Y1 - 1991/1/1
N2 - The active forward movement of cells is often associated with the rearward transport of particles over the surfaces of their lamellae. Unlike the rest of the lamella, we found that the leading edge (within 0.5 microns of the cell boundary) is specialized for rearward transport of membrane-bound particles, such as Con A-coated latex microspheres. Using a single-beam optical gradient trap (optical tweezers) to apply restraining forces to particles, we can capture, move and release particles at will. When first bound on the central lamellar surface, Con A-coated particles would diffuse randomly; when such bound particles were brought to the leading edge of the lamella with the optical tweezers, they were often transported rearward. As in our previous studies, particle transport occurred with a concurrent decrease in apparent diffusion coefficient, consistent with attachment to the cytoskeleton. For particles at the leading edge of the lamella, weak attachment to the cytoskeleton and transport occurred with a half-time of 3 s; equivalent particles elsewhere on the lamella showed no detectable attachment when monitored for several minutes. Particles held on the cell surface by the laser trap attached more strongly to the cytoskeleton with time. These particles could escape a trapping force of 0.7 × 10-6 dyne after 18 ± 14 (sd) s at the leading edge, and after 64 ± 34 (SD) s elsewhere on the lamella. Fluorescent succinylated Con A staining showed no corresponding concentration of general glycoproteins at the leading edge, but cytochalasin D-resistant filamentous actin was found at the leading edge. Our results have implications for cell motility: if the forces used for rearward particle transport were applied to a rigid substratum, cells would move forward. Such a mechanism would be most efficient if the leading edge of the cell contained preferential sites for attachment and transport.
AB - The active forward movement of cells is often associated with the rearward transport of particles over the surfaces of their lamellae. Unlike the rest of the lamella, we found that the leading edge (within 0.5 microns of the cell boundary) is specialized for rearward transport of membrane-bound particles, such as Con A-coated latex microspheres. Using a single-beam optical gradient trap (optical tweezers) to apply restraining forces to particles, we can capture, move and release particles at will. When first bound on the central lamellar surface, Con A-coated particles would diffuse randomly; when such bound particles were brought to the leading edge of the lamella with the optical tweezers, they were often transported rearward. As in our previous studies, particle transport occurred with a concurrent decrease in apparent diffusion coefficient, consistent with attachment to the cytoskeleton. For particles at the leading edge of the lamella, weak attachment to the cytoskeleton and transport occurred with a half-time of 3 s; equivalent particles elsewhere on the lamella showed no detectable attachment when monitored for several minutes. Particles held on the cell surface by the laser trap attached more strongly to the cytoskeleton with time. These particles could escape a trapping force of 0.7 × 10-6 dyne after 18 ± 14 (sd) s at the leading edge, and after 64 ± 34 (SD) s elsewhere on the lamella. Fluorescent succinylated Con A staining showed no corresponding concentration of general glycoproteins at the leading edge, but cytochalasin D-resistant filamentous actin was found at the leading edge. Our results have implications for cell motility: if the forces used for rearward particle transport were applied to a rigid substratum, cells would move forward. Such a mechanism would be most efficient if the leading edge of the cell contained preferential sites for attachment and transport.
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U2 - 10.1083/jcb.114.5.1029
DO - 10.1083/jcb.114.5.1029
M3 - Article
VL - 114
SP - 1029
EP - 1036
JO - Journal of Cell Biology
JF - Journal of Cell Biology
SN - 0021-9525
IS - 5
ER -