RhoA function in lamellae formation and migration is regulated by the alpha6beta4 integrin and cAMP metabolism.
RhoA function in lamellae formation and migration is regulated by the alpha6beta4 integrin and cAMP metabolism.
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DOI：
10.1083/jcb.148.2.253
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发表时间：
2000-01-24
期刊：
影响因子：
--
通讯作者：
Mercurio AM
中科院分区：
文献类型：
--
作者：
O'Connor KL;Nguyen BK;Mercurio AM
克隆A结肠癌细胞形成扇形层粘连，当铺在层粘连蛋白上时表现出随机迁移，该过程依赖于α6β4整联蛋白的连接。在这里，我们报告了在克隆A细胞中显性负性RhoA（N19RhoA）的表达抑制α6β4依赖性膜皱褶、层粘连形成和迁移。相反，显性负Rac（N17Rac 1）的表达对这些过程没有影响。使用Rhotekin结合测定来评估RhoA活化，我们观察到与保持在悬浮液中或在胶原上铺板的细胞相比，通过抗体介导的聚集或层粘连蛋白附着的α6β4的接合导致RhoA活化增加2至3倍。然而，抗体介导的β1整联蛋白聚集实际上抑制了Rho A活化。α6β4介导的克隆A细胞与层粘连蛋白的相互作用促进了RhoA从细胞质移位到层粘连蛋白边缘的膜皱褶，并促进了其与β1整合素的共定位，如通过免疫荧光显微镜所评估的。此外，RhoA易位通过抑制磷酸二酯酶活性而被阻断，并通过抑制cAMP依赖性蛋白激酶的活性而被增强。总之，这些结果建立了一个特定的整合素介导的途径RhoA的激活，是由cAMP调节，并在laminate的形成和迁移的功能。
Clone A colon carcinoma cells develop fan-shaped lamellae and exhibit random migration when plated on laminin, processes that depend on the ligation of the α6β4 integrin. Here, we report that expression of a dominant negative RhoA (N19RhoA) in clone A cells inhibited α6β4-dependent membrane ruffling, lamellae formation, and migration. In contrast, expression of a dominant negative Rac (N17Rac1) had no effect on these processes. Using the Rhotekin binding assay to assess RhoA activation, we observed that engagement of α6β4 by either antibody-mediated clustering or laminin attachment resulted in a two- to threefold increase in RhoA activation, compared with cells maintained in suspension or plated on collagen. Antibody-mediated clustering of β1 integrins, however, actually suppressed Rho A activation. The α6β4-mediated interaction of clone A cells with laminin promoted the translocation of RhoA from the cytosol to membrane ruffles at the edges of lamellae and promoted its colocalization with β1 integrins, as assessed by immunofluorescence microscopy. In addition, RhoA translocation was blocked by inhibiting phosphodiesterase activity and enhanced by inhibiting the activity of cAMP-dependent protein kinase. Together, these results establish a specific integrin-mediated pathway of RhoA activation that is regulated by cAMP and that functions in lamellae formation and migration.
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Rho GTPases控制细胞运动过程中的极性，突出和粘附。
影响因子：
7.8
作者：
Nobes, C D;Hall, A
通讯作者：
Hall, A
影响因子：
5.3
作者：
NISHIYAMA, T;SASAKI, T;TAKAI, Y
通讯作者：
TAKAI, Y
影响因子：
7.5
作者：
Borradori, L;Sonnenberg, A
通讯作者：
Sonnenberg, A
DOI：
10.1083/jcb.146.5.1147
发表时间：
1999-09-06
期刊：
The Journal of cell biology
影响因子：
--
作者：
Rabinovitz I;Toker A;Mercurio AM
通讯作者：
Mercurio AM
影响因子：
4.8
作者：
Yoshioka, K;Matsumura, F;Itoh, K
通讯作者：
Itoh, K