Hic-5 promotes endothelial cell migration to lysophosphatidic acid
Hic-5 promotes endothelial cell migration to lysophosphatidic acid
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DOI：
10.1152/ajpheart.00728.2006
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发表时间：
2007-07-01
影响因子：
4.8
通讯作者：
Panetti, T. S.
中科院分区：
文献类型：
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作者：
Avraamides, C.;Bromberg, M. E.;Panetti, T. S.
内皮细胞迁移对于血管的正常发育至关重要。来自生长因子和基质蛋白的信号通过粘着斑蛋白整合以改变细胞迁移。过氧化氢诱导的克隆5（Hic-5）是桩蛋白家族的成员，在牛肺动脉内皮（BPAE）细胞的粘着斑中富集，其迁移到变性胶原上的溶血磷脂酸（LPA）。在这项研究中，我们研究了Hic-5在LPA刺激的内皮细胞迁移中的作用。LPA招募Hic-5到粘附灶和胶原上接种的BPAE细胞中的伪足，表明Hic-5到粘附灶的招募与内皮细胞迁移相关。内源性Hic-5的敲低显著降低了向LPA的迁移，证实了Hic-5参与迁移。为了阐明Hic-5在内皮细胞迁移中的作用，我们在BPAE细胞中外源表达野生型（WT）Hic-5和绿色荧光蛋白Hic-5 C369 A/C372 A（LIM 3突变体）构建体。WT Hic-5表达增加BPAE细胞对LPA的趋化性，而表达绿色荧光蛋白Hic-5 C369 A/C372 A的细胞向LPA的迁移与载体对照细胞中所示的相似。此外，在WT Hic-5细胞中，ERK磷酸化在LPA存在下增强。MEK活性的药理学抑制剂抑制LPA刺激的WT Hic-5细胞迁移和ERK磷酸化，表明Hic-5通过MEK激活ERK增强迁移。总之，这些研究表明，Hic-5，在内皮细胞中的粘着斑蛋白，被招募到伪足在LPA的存在下，并增强迁移。
Endothelial cell migration is critical for proper blood vessel development. Signals from growth factors and matrix proteins are integrated through focal adhesion proteins to alter cell migration. Hydrogen peroxide-inducible clone 5 (Hic-5), a paxillin family member, is enriched in the focal adhesions in bovine pulmonary artery endothelial (BPAE) cells, which migrate to lysophosphatidic acid (LPA) on denatured collagen. In this study, we investigate the role of Hic-5 in LPA-stimulated endothelial cell migration. LPA recruits Hic-5 to the focal adhesions and to the pseudopodia in BPAE cells plated on collagen, suggesting that recruitment of Hic-5 to focal adhesions is associated with endothelial cell migration. Knockdown of endogenous Hic-5 significantly decreases migration toward LPA, confirming involvement of Hic-5 in migration. To address the role of Hic-5 in endothelial cell migration, we exogenously expressed wild-type (WT) Hic-5 and green fluorescent protein Hic-5 C369A/C372A (LIM3 mutant) constructs in BPAE cells. WT Hic-5 expression increases chemotaxis of BPAE cells to LPA, whereas migration toward LPA of the green fluorescent protein Hic-5 C369A/C372A-expressing cells is similar to that shown in vector control cells. Additionally, ERK phosphorylation is enhanced in the presence of LPA in WT Hic-5 cells. A pharmacological inhibitor of MEK activity inhibits LPA-stimulated WT Hic-5 cell migration and ERK phosphorylation, suggesting Hic-5 enhances migration via MEK activation of ERK. Together, these studies indicate that Hic-5, a focal adhesion protein in endothelial cells, is recruited to the pseudopodia in the presence of LPA and enhances migration.