Evidence for an actin-containing cytoplasmic precursor of the focal contact and the timing of incorporation of vinculin at the focal contact.
Evidence for an actin-containing cytoplasmic precursor of the focal contact and the timing of incorporation of vinculin at the focal contact.
复制标题
DOI：
10.1083/jcb.105.6.2803
复制
发表时间：
1987-12
影响因子：
7.8
通讯作者：
Izzard, C S
中科院分区：
文献类型：
--
作者：
DePasquale, J A;Izzard, C S
用硝基苯并恶二唑（NBD）-鬼笔菌素（phallacidin）和间接免疫荧光染色法，分别观察了F-actin和vinculin在鸡胚成纤维细胞中的分布，并在固定染色前，用微分干涉对比（DIC）或干涉反射显微镜（IRIS）记录细胞的运动，将其与焦点接触形成过程联系起来。线性细胞质前体的焦点接触，存在于独立的板状伪足，染色强烈与NBD-鬼笔毒肽。无一例外，新的焦点接触，8秒及以上的固定，与一个较长的F-肌动蛋白肋板状体或，在旧的接触，F-肌动蛋白结构的相似尺寸的接触。这种变化的F-肌动蛋白的分布在新的接触占的隔离的结构前体成一个附着的部分，在焦点接触和一个单独的运动部分。这些结果表明，F-肌动蛋白积聚在邻近膜区域的前体中，该膜区域能够形成焦点接触，并且与这种F-肌动蛋白有助于与新接触相关的初始粘附斑块的解释一致。运动的板状伪足中基本上不存在纤维蛋白，没有显示出与富含F-肌动蛋白的前体或非常年轻的病灶接触的优先关联，但是在90年代期间在新接触中积累。因此，F-肌动蛋白与膜的关联在最初的局部接触之前并持续存在，这与黏着斑蛋白无关，黏着斑蛋白在局部接触发展中的作用仍不清楚。
The distribution of F-actin and vinculin in chicken embryo fibroblasts has been examined by nitrobenzoxadiazol (NBD)-phallacidin and indirect immunofluorescent staining, respectively, and related to the process of focal contact formation by recording the motility of the cell with differential interference contrast (DIC) or interference reflection microscopy (IRM) before fixation for staining. Linear cytoplasmic precursors of the focal contact, present within unattached lamellipodia, stained intensely with NBD-phallacidin. Without exception new focal contacts, 8 s and older at fixation, were associated with either a longer F-actin rib in the lamellipodium or, in older contacts, an F-actin structure of similar dimensions to the contact. This change in distribution of F-actin over the new contacts was accounted for by the segregation of the structural precursor into an attached part over the focal contact and a separate motile part. These results show that F- actin accumulates in the precursor adjacent to areas of the membrane competent to form the focal contact, and are consistent with the interpretation that this F-actin contributes to the initial adhesion plaque associated with the new contact. Vinculin was essentially absent from motile lamellipodia, showed no preferential association with F- actin rich precursors or very young focal contacts, but accumulated over new contacts during a 90-s period. Therefore, the association of F- actin with the membrane that precedes and persists in the initial focal contact is independent of vinculin, and the role of vinculin in development of the focal contact remains unclear.