Clustering of Syndecan-4 and Integrin β1 by Laminin α3 Chain-derived Peptide Promotes Keratinocyte Migration
Clustering of Syndecan-4 and Integrin β1 by Laminin α3 Chain-derived Peptide Promotes Keratinocyte Migration
复制标题
DOI：
10.1091/mbc.e08-09-0977
复制
发表时间：
2009-07-01
影响因子：
3.3
通讯作者：
Utani, Atsushi
中科院分区：
文献类型：
--
作者：
Araki, Eri;Momota, Yutaka;Utani, Atsushi
多配体在细胞扩散中充当细胞外基质 (ECM) 的受体，并具有整合素。然而，它们具体参与细胞迁移或伤口愈合的分子机制尚未阐明。在这里，我们报道了一种合成肽 PEP75，它含有层粘连蛋白 α 3LG4 模块的多聚糖结合序列，可在体外和体内诱导角质形成细胞迁移。可溶性 PEP75 诱导 syndecan-4 和构象修饰的整联蛋白 β 1 的聚集，与 syndecan-4 在可溶性 PEP75 诱导的簇中共定位。用 PEP75 处理溶液中的细胞导致在免疫染色和流式细胞术中暴露出整合素 β 1 的 P4G11 抗体表位，并增强了整合素 β 1 依赖性细胞对 ECM 的粘附。 Pulldown 测定表明，PEP75 与 syndecan-4 结合，但不与整合素 beta 1 结合。一项 siRNA 研究揭示了 syndecan-4 在 PEP75 诱导的 P4G11 抗体结合上调和 HaCaT 细胞迁移中的作用。我们得出的结论是，可溶性 PEP75 与 syndecan-4 的结合诱导了整合素 β 1 的偶联，这与整合素 β 1 构象的变化和激活有关，并导致角质形成细胞迁移。通过多配体激活整合素功能可能是治疗慢性伤口的一种新方法。
Syndecans function as receptors for extracellular matrix (ECM) with integrins in cell spreading. However, the molecular mechanism of their specific involvement in cell migration or in wound healing has not been elucidated yet. Here, we report that a synthetic peptide, PEP75, which contains the syndecan-binding sequence of the laminin alpha 3LG4 module, induces keratinocyte migration in in vitro and in vivo. Soluble PEP75 induced the clustering of syndecan-4 and conformation-modified integrin beta 1 colocalized with syndecan-4 in soluble PEP75-induced clusters. Treatment of cells in solution with PEP75 resulted in the exposure of the P4G11 antibody epitope of integrin beta 1 in immunostaining as well as in flow cytometry and augmented integrin beta 1-dependent cell adhesion to ECM. Pulldown assays demonstrated that PEP75 bound to syndecan-4, but not to integrin beta 1. A siRNA study revealed a role for syndecan-4 in PEP75-induced up-regulation of P4G11 antibody binding and migration of HaCaT cells. We conclude that binding of soluble PEP75 to syndecan-4 induces the coupling of integrin beta 1, which is associated with integrin beta 1-conformational changes and activation, and leads to keratinocyte migration. To activate integrin function through syndecans could be a novel therapeutic approach for chronic wound.