Adhesion dynamics and cytoskeletal structure of gliding human fibrosarcoma cells: a hypothetical model of cell migration.
During motility of fibroblast type cells on planar surfaces, adhesions are formed at the anterior of the protruding lamella, which remain stationary relative to the substrate and undergo a maturation process as the cell passes over them. Through these adhesions force is exerted, the orientation of which is parallel to the direction of the movement. Here we show that, during gliding-type motility of human tumor cells, characterized by a semicircular shape, adhesions were found at the outer rim of the cells, along the semicircle. Time-lapse microscopy of GFP-vinculin-expressing cells showed that these adhesions were constantly renewed at the cell edge and followed a curved trajectory according to the graded radial extension model. Eventually, the adhesions reached the long axis of the cell where they were retracted into the cell body. Actin cables formed arcs, with the concave face at the anterior of the lamella found to be oriented in the direction of movement. Since adhesions moved backward with respect to the cell, actin cables connected to these adhesions must continuously grow, reaching maximal size at the long axis of the cell. Contraction of the arcs is responsible for the forward movement of the cell body.
Paku
Sándor
S
Department of Molecular Pathology, Joint Research Organization of the Hungarian Academy of Sciences, Budapest, Hungary. paku@korb1.sote.hu
Tóvári
József
J
Lörincz
Zsolt
Z
Timár
Ferenc
F
Döme
Balázs
B
Kopper
László
L
Raz
Avraham
A
Tímár
József
J
D002448:Cell Adhesion; D002450:Cell Communication; D002465:Cell Movement; D003599:Cytoskeleton / Q000378:metabolism*; D005354:Fibrosarcoma / Q000473:pathology*; D005455:Fluorescent Antibody Technique; D049452:Green Fluorescent Proteins; D006801:Humans; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008857:Microscopy, Interference; D008954:Models, Biological; D013997:Time Factors; D014407:Tumor Cells, Cultured / Q000473:pathology; D016596:Vinculin / Q000235:genetics / Q000378:metabolism
D008164:Luminescent Proteins; D016596:Vinculin; D049452:Green Fluorescent Proteins