Phosphoinositide-3 kinase-Rac1-c-Jun NH2-terminal kinase signaling mediates collagen I-induced cell scattering and up-regulation of N-cadherin expression in mouse mammary epithelial cells
Phosphoinositide-3 kinase-Rac1-c-Jun NH2-terminal kinase signaling mediates collagen I-induced cell scattering and up-regulation of N-cadherin expression in mouse mammary epithelial cells
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DOI：
10.1091/mbc.e05-12-1123
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发表时间：
2006-07-01
影响因子：
3.3
通讯作者：
Johnson, Keith R.
中科院分区：
文献类型：
--
作者：
Shintani, Yasushi;Wheelock, Margaret J.;Johnson, Keith R.
在上皮-间充质转化（EMT）过程中，细胞必须以同步的方式改变它们彼此之间以及与它们的细胞外基质的相互作用。为了表征细胞用于协调这些变化的信号通路，我们使用NMuMG乳腺上皮细胞。我们发现，这些细胞成为成纤维细胞和分散，增加N-钙粘蛋白的表达时，培养在胶原蛋白I。Rac 1和c-Jun NH 2-末端激酶（JNK）被激活时，细胞接种在胶原蛋白I，显性抑制Rac 1（RacN 17）或抑制JNK信号阻止胶原蛋白I诱导的形态学变化和N-钙粘蛋白上调。此外，抑制磷脂酰肌醇-3激酶（PI 3 K）的活性阻止Rac 1和JNK的激活以及胶原I诱导的N-钙粘蛋白上调。这些数据暗示了NMuMG细胞中胶原I诱导的变化中的PI 3 K-Rac 1-JNK信号传导。为了建立一个角色，N-钙粘蛋白在胶原蛋白I诱导的细胞散射，我们产生了N-钙粘蛋白过表达和敲低NMuMG细胞，并表明敲低N-钙粘蛋白表达防止胶原蛋白I诱导的形态学变化。运动分析表明，细胞过度表达N-钙粘蛋白显着更能动性比模拟转染细胞和N-钙粘蛋白介导的运动是胶原蛋白I依赖。此外，我们发现，索形成和分支在三维培养（EMT依赖性事件）需要N-钙粘蛋白的表达和PI 3 K-Rac 1-JNK信号。
During epithelial-to-mesenchymal transitions (EMTs), cells must change their interactions with one another and with their extracellular matrix in a synchronized manner. To characterize signaling pathways cells use to coordinate these changes, we used NMuMG mammary epithelial cells. We showed that these cells become fibroblastic and scattered, with increased N-cadherin expression when cultured on collagen I. Rac1 and c-Jun NH2-terminal kinase (JNK) were activated when cells were plated on collagen I, and dominant inhibitory Rac1 (RacN17) or inhibition of JNK signaling prevented collagen I-induced morphological changes and N-cadherin up-regulation. Furthermore, inhibiting phosphoinositide-3 kinase (PI3K) activity prevented Rac1 and JNK activation as well as collagen I-induced N-cadherin up-regulation. These data implicate PI3K-Rac1-JNK signaling in collagen I-induced changes in NMuMG cells. To establish a role for N-cadherin in collagen I-induced cell scattering, we generated N-cadherin overexpressing and knockdown NMuMG cells and showed that knocking down N-cadherin expression prevented collagen I-induced morphological changes. Motility assays showed that cells overexpressing N-cadherin were significantly more motile than mock-transfected cells and that N-cadherin-mediated motility was collagen I dependent. In addition, we showed that cord formation and branching in three-dimensional culture (EMT-dependent events) required N-cadherin expression and PI3K-Rac1-JNK signaling.