Role of cofilin in epidermal growth factor-stimulated actin polymerization and lamellipod protrusion.
Role of cofilin in epidermal growth factor-stimulated actin polymerization and lamellipod protrusion.
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DOI：
10.1083/jcb.148.3.531
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发表时间：
2000-02-07
期刊：
影响因子：
--
通讯作者：
Condeelis JS
中科院分区：
文献类型：
--
作者：
Chan AY;Bailly M;Zebda N;Segall JE;Condeelis JS
用表皮生长因子 (EGF) 刺激转移性 MTLn3 细胞会导致肌动蛋白成核活性快速而短暂地增加，这是由于在延伸的片状足的最前缘出现了游离的倒刺末端。为了研究肌动蛋白丝切蛋白在 MTLn3 细胞中 EGF 刺激的肌动蛋白聚合和片状足延伸中的作用，我们详细检查了肌动蛋白丝切蛋白相对于自由倒刺末端的时间和空间分布，并通过测量肌动蛋白丝数量的变化来表征肌动蛋白动力学。 EGF 刺激会触发膜附近前缘的肌丝蛋白丝切蛋白短暂增加，这与那里自由倒刺末端的出现恰好同时发生。脱氧核糖核酸酶 I 结合测定显示，EGF 刺激后，每个细胞的细丝数量增加了 1.5 倍。使用脱氧核糖核酸酶 I 结合对尖端进行原位检测表明，尖端数量的增加仅限于前缘隔室，并且不会发生在应力纤维内或一般细胞质中。使用光学显微镜切断测定，直接在细胞提取物中观察到丝切蛋白的切断活性，并显示在用 EGF 刺激细胞后被激活。显微注射针对丝切蛋白的功能阻断抗体可抑制 EGF 刺激后前缘处游离倒刺末端和片状足突出的出现。这些结果支持这样一种模型：EGF 刺激将肌动蛋白丝切蛋白募集到其切断活性被激活的前缘，从而导致具有自由倒刺末端的短肌动蛋白丝的生成，参与肌动蛋白聚合的成核。
Stimulation of metastatic MTLn3 cells with epidermal growth factor (EGF) causes a rapid and transient increase in actin nucleation activity resulting from the appearance of free barbed ends at the extreme leading edge of extending lamellipods. To investigate the role of cofilin in EGF-stimulated actin polymerization and lamellipod extension in MTLn3 cells, we examined in detail the temporal and spatial distribution of cofilin relative to free barbed ends and characterized the actin dynamics by measuring the changes in the number of actin filaments. EGF stimulation triggers a transient increase in cofilin in the leading edge near the membrane, which is precisely cotemporal with the appearance of free barbed ends there. A deoxyribonuclease I binding assay shows that the number of filaments per cell increases by 1.5-fold after EGF stimulation. Detection of pointed ends in situ using deoxyribonuclease I binding demonstrates that this increase in the number of pointed ends is confined to the leading edge compartment, and does not occur within stress fibers or in the general cytoplasm. Using a light microscope severing assay, cofilin's severing activity was observed directly in cell extracts and shown to be activated after stimulation of the cells with EGF. Microinjection of function-blocking antibodies against cofilin inhibits the appearance of free barbed ends at the leading edge and lamellipod protrusion after EGF stimulation. These results support a model in which EGF stimulation recruits cofilin to the leading edge where its severing activity is activated, leading to the generation of short actin filaments with free barbed ends that participate in the nucleation of actin polymerization.
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影响因子：
64.8
作者：
Loisel, TP;Boujemaa, R;Carlier, MF
通讯作者：
Carlier, MF
影响因子：
4.8
作者：
AIZAWA, H;SUTOH, K;YAHARA, I
通讯作者：
YAHARA, I
影响因子：
3.7
作者：
ABERCROMBIE, M;HEAYSMAN, JE;PEGRUM, SM
通讯作者：
PEGRUM, SM
DOI：
10.1083/jcb.146.6.1319
发表时间：
1999-09-20
期刊：
The Journal of cell biology
影响因子：
--
作者：
Egile C;Loisel TP;Laurent V;Li R;Pantaloni D;Sansonetti PJ;Carlier MF
通讯作者：
Carlier MF
DOI：
10.1083/jcb.105.6.2817
发表时间：
1987-12
期刊：
The Journal of cell biology
影响因子：
--
作者：
Bamburg JR;Bray D
通讯作者：
Bray D