p21-activated kinase 1 (Pak1) regulates cell motility in mammalian fibroblasts.
p21-activated kinase 1 (Pak1) regulates cell motility in mammalian fibroblasts.
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DOI：
10.1083/jcb.145.4.837
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发表时间：
1999-05-17
期刊：
影响因子：
--
通讯作者：
Chernoff J
中科院分区：
文献类型：
--
作者：
Sells MA;Boyd JT;Chernoff J
P21(CDC42/RAC)激活的PK1在大多数真核细胞中调节细胞形态和极性。我们和其他人已经确定，Pak对这些参数的影响是通过皮质肌动蛋白组织的变化来调节的。因为细胞运动需要肌动蛋白/肌球蛋白细胞骨架的极化重排，所以我们研究了Ak1在调节细胞运动中的作用。我们建立了受四环素调控的克隆性NIH-3T3细胞系，该细胞系可诱导表达野生型、蛋白酪氨酸酶和活性蛋白，并对这些细胞的形态、F-肌动蛋白组织和运动性进行了检测。任何这些形式的pak1的表达都会导致肌动蛋白组织发生戏剧性的变化，这种变化不会被显性-负性形式的rac1的共同表达所抑制。诱导表达野生型或结构性活性的pak1的细胞在前沿有大的极化片状脂膜，当被涂在纤维连接蛋白覆盖的表面时，比正常的细胞更活跃，并对固定的胶原梯度表现出增强的定向运动。相反，表达一种蛋白激酶1死亡形式的细胞投射出同时从细胞不同部分出现的多个片状脂肪。这些细胞虽然具有很高的运动性，但当被移植到纤维连接蛋白涂层的表面时，运动的持续性降低，并且在定向运动到固定的胶原蛋白方面存在缺陷。蛋白激酶1的表达伴随着肌球蛋白轻链(MLC)磷酸化的增加，而蛋白激酶失活的蛋白1的表达对肌球蛋白轻链(MLC)的磷酸化没有影响。这些结果表明，pak1影响MLC的磷酸化状态，从而将该激酶与直接影响细胞运动的分子联系起来。
The p21 (Cdc42/Rac) activated kinase Pak1 regulates cell morphology and polarity in most, if not all, eukaryotic cells. We and others have established that Pak's effects on these parameters are mediated by changes in the organization of cortical actin. Because cell motility requires polarized rearrangements of the actin/myosin cytoskeleton, we examined the role of Pak1 in regulating cell movement. We established clonal tetracycline-regulated NIH-3T3 cell lines that inducibly express either wild-type Pak1, a kinase-dead, or constitutively-active forms of this enzyme, and examined the morphology, F-actin organization, and motility of these cells. Expression of any of these forms of Pak1 induced dramatic changes in actin organization which were not inhibited by coexpression of a dominant-negative form of Rac1. Cells inducibly expressing wild-type or constitutively-active Pak1 had large, polarized lamellipodia at the leading edge, were more motile than their normal counterparts when plated on a fibronectin-coated surface, and displayed enhanced directional movement in response to an immobilized collagen gradient. In contrast, cells expressing a kinase-dead form of Pak1 projected multiple lamellipodia emerging from different parts of the cell simultaneously. These cells, though highly motile, displayed reduced persistence of movement when plated on a fibronectin-coated surface and had defects in directed motility toward immobilized collagen. Expression of constitutively activated Pak1 was accompanied by increased myosin light chain (MLC) phosphorylation, whereas expression of kinase-dead Pak1 had no effect on MLC. These results suggest that Pak1 affects the phosphorylation state of MLC, thus linking this kinase to a molecule that directly affects cell movement.
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影响因子：
11.4
作者：
Daniels, RH;Hall, PS;Bokoch, GM
通讯作者：
Bokoch, GM
影响因子：
4.8
作者：
Amano, M;Ito, M;Kaibuchi, K
通讯作者：
Kaibuchi, K
影响因子：
64.8
作者：
King, AJ;Sun, HY;Marshall, MS
通讯作者：
Marshall, MS
影响因子：
11.4
作者：
LEBERER, E;DIGNARD, D;WHITEWAY, M
通讯作者：
WHITEWAY, M
DOI：
10.1083/jcb.141.5.1147
发表时间：
1998-06-01
期刊：
The Journal of cell biology
影响因子：
--
作者：
Allen WE;Zicha D;Ridley AJ;Jones GE
通讯作者：
Jones GE