Lysophosphatidic acid and microtubule-destabilizing agents stimulate fibronectin matrix assembly through Rho-dependent actin stress fiber formation and cell contraction
Lysophosphatidic acid and microtubule-destabilizing agents stimulate fibronectin matrix assembly through Rho-dependent actin stress fiber formation and cell contraction
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DOI：
10.1091/mbc.8.8.1415
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发表时间：
1997-08-01
影响因子：
3.3
通讯作者：
Mosher, DF
中科院分区：
文献类型：
--
作者：
Zhang, QH;Magnusson, MK;Mosher, DF
纤连蛋白 (FN) 基质组装是一种细胞依赖性过程，由 FN 70 kDa 氨基末端区域的细胞表面结合位点介导。我们最近证明溶血磷脂酸 (LPA) 是 FN 基质组装的刺激剂。微管的破坏已被证明可以模仿 LPA 的一些细胞内效应，包括肌动蛋白应力纤维的形成和肌球蛋白轻链磷酸化。我们比较了微管破坏和 LPA 对 FN 结合和肌动蛋白细胞骨架组织的影响。诺考达唑或长春碱对微管的破坏增加了 FN 与贴壁细胞的结合。结合位点的调节是快速、动态且可逆的。增强的结合是由于结合位点的数量和亲和力的增加。这些作用类似于 LPA 对 FN 结合的作用。诺考达唑诱导的结合可被微管稳定剂紫杉醇抑制，但不能被一定浓度的磷脂酶 B 预处理所抑制，从而完全消除 LPA 的刺激作用。荧光显微镜揭示了肌动蛋白应力纤维形成、细胞收缩和 FN 结合之间的密切相关性。阻断小 GTP 结合蛋白 Rho 或肌动蛋白-肌球蛋白相互作用可抑制诺考达唑和 LPA 对 FN 结合的作用。这些观察结果表明，Rho 依赖性肌动蛋白应力纤维的形成和细胞收缩会诱导 FN 结合增加，并代表细胞调节 FN 基质组装的快速不稳定方式。
Fibronectin (FN) matrix assembly is a cell-dependent process mediated by cell surface-binding sites for the 70-kDa amino-terminal region of FN. We have shown recently that lysophosphatidic acid (LPA) is a stimulator of FN matrix assembly. Disruption of microtubules has been shown to mimic some of the intracellular effects of LPA including the formation of actin stress fibers and myosin light chain phosphorylation. We compared the effects of microtubule disruption and LPA on FN binding and actin cytoskeleton organization. The disruption of microtubules by nocodazole or vinblastine increased FN binding to adherent cells. The modulation of binding sites was rapid, dynamic, and reversible. Enhanced binding was due to increases in both the number and affinity of binding sites. These effects are similar to the effects of LPA on FN binding. Binding induced by nocodazole was inhibited by the microtubule-stabilizing agent Taxol but not by pretreatment with a concentration of phospholipase B that totally abolished the stimulatory effect of LPA. Fluorescence microscopy revealed a close correlation among actin stress fiber formation, cell contraction, and FN binding. Blockage of the small GTP binding protein Rho or actin-myosin interactions inhibited the effects of both nocodazole and LPA on FN binding. These observations demonstrate that Rho-dependent actin stress fiber formation and cell contraction induce increased FN binding and represent a rapid labile way that cells can modulate FN matrix assembly.