Paku Sándor, Tóvári József, Lörincz Zsolt, Timár Ferenc, Döme Balázs, Kopper László, Raz Avraham, Tímár József
Department of Molecular Pathology, Joint Research Organization of the Hungarian Academy of Sciences, Budapest, Hungary.
Exp Cell Res. 2003 Nov 1;290(2):246-53. doi: 10.1016/s0014-4827(03)00334-3.
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.
在成纤维细胞型细胞在平面上运动期间，黏附在突出片状伪足的前端形成，这些黏附相对于底物保持静止，并在细胞越过它们时经历成熟过程。通过这些黏附施加力，其方向与运动方向平行。在这里我们表明，在以半圆形为特征的人类肿瘤细胞的滑行型运动期间，在细胞的外缘沿半圆发现了黏附。对表达绿色荧光蛋白-纽蛋白的细胞进行延时显微镜观察表明，这些黏附在细胞边缘不断更新，并根据分级径向延伸模型遵循弯曲轨迹。最终，黏附到达细胞的长轴，在那里它们被回缩到细胞体中。肌动蛋白束形成弧形，其凹面位于片状伪足的前端，发现其方向与运动方向一致。由于黏附相对于细胞向后移动，连接到这些黏附的肌动蛋白束必须不断生长，在细胞的长轴处达到最大尺寸。弧形的收缩负责细胞体的向前运动。
