N-formyl peptide receptor ligation induces Rac-dependent actin reorganization through Gβγ subunits and class Ia phosphoinositide 3-kinases
N-formyl peptide receptor ligation induces Rac-dependent actin reorganization through Gβγ subunits and class Ia phosphoinositide 3-kinases
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DOI：
10.1074/jbc.m002743200
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发表时间：
2000-08-25
影响因子：
4.8
通讯作者：
Abo, A
中科院分区：
文献类型：
--
作者：
Belisle, B;Abo, A
N-甲酰肽受体是一种G蛋白偶联的跨膜受体，参与刺激中性粒细胞中的多种差异反应，包括趋化性、脱粒、超氧化物产生、转录激活和肌动蛋白重组。虽然已知N-甲酰基-Met-Leu-Phe诱导肌动蛋白重组，但从受体到肌动蛋白细胞骨架的事件顺序尚未得到很好的表征。为了研究从N-甲酰肽受体到肌动蛋白细胞骨架的信号通路，我们开发了一个模型系统，利用显微注射技术与非造血细胞系。将编码N-甲酰肽受体的表达载体显微注射到猪主动脉内皮细胞中，并用N-甲酰-Met-Leu-Phe刺激以诱导肌动蛋白重组和膜皱褶。受体介导的信号被百日咳毒素和显性阴性Rac-N17阻断，分别表明G（1）α亚基和小的鸟苷三磷酸酶Rac参与。此外，G β γ亚基和磷脂酰肌醇（PI）3-激酶α的膜靶向形式足以诱导类似的肌动蛋白重组，PI 3-激酶与N-甲酰肽受体的各种突变体的共表达确定了与Ia类PI-3激酶介导的肌动蛋白重组的联系。
The N-formyl peptide receptor is a G protein-coupled transmembrane receptor involved in stimulating a variety of differential responses in neutrophils including chemotaxis, degranulation, superoxide production, transcriptional activation, and actin reorganization. Although it is known that N-formyl-Met-Leu-Phe induces actin reorganization, the sequence of events from the receptor to the actin cytoskeleton is not well characterized. To study the signaling pathway from the N-formyl peptide receptor to the actin cytoskeleton, we developed a model system utilizing microinjection techniques with a nonhematopoietic cell line. An expression vector coding for the N-formyl peptide receptor was microinjected into porcine aortic endothelial cells and stimulated with N-formyl-Met-Leu-Phe to induce actin reorganization and membrane ruffling. The receptor-mediated signal was blocked by pertussis toxin and by a dominant negative Rac-N17, indicating the involvement of G(1)alpha subunit and the small guanosine triphosphatase Rac, respectively. Moreover, G beta gamma subunits and membrane targeted forms of phosphatidylinositol (PI) 3-kinase alpha were sufficient to induce similar actin reorganization, and coexpression of various mutants of PI 3-kinase with the N-formyl peptide receptor identified a link to class Ia PI-3 kinase-mediated actin reorganization.