Cooperation between β- and γ-cytoplasmic actins in the mechanical regulation of endothelial microparticle formation
Cooperation between β- and γ-cytoplasmic actins in the mechanical regulation of endothelial microparticle formation
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DOI：
10.1096/fj.12-216531
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发表时间：
2013-02-01
期刊：
影响因子：
4.8
通讯作者：
Combes, Valery
中科院分区：
文献类型：
--
作者：
Latham, Sharissa L.;Chaponnier, Christine;Combes, Valery
在许多疾病中观察到内皮微粒（MP）水平升高，作为血管功能障碍的效应物和有价值的标志物越来越多地支持作用。虽然肌动蛋白细胞骨架的收缩作用与囊泡形成有关，即，MP生产，其成分，β-和γ-细胞质肌动蛋白的精确相互作用和机制是未知的。人脑微血管内皮细胞刺激与已知的激动剂，并通过扫描电子显微镜（SEM）和流式细胞术监测囊泡形成的发展。这些数据相结合，提供了新的见解的动力学，模式的囊泡细胞招聘，和特定的刺激的反应程度。重组β-和γ-肌动蛋白，F-肌动蛋白，黏着斑蛋白，和塔林伴随着显着的MP释放。刺激后β-肌动蛋白重新分布到基底应力纤维中与增加的位于顶端的富含肌动蛋白的颗粒结构相关，这反过来又与通过SEM观察到的电子透明膜突起直接相关。Y-27632 Rho-激酶抑制作用消除了基底β-肌动蛋白纤维的形成，使顶端相关的富含肌动蛋白的结构最小化，显著降低了膜突起和MP释放至接近基底水平。细胞骨架蛋白的表达和分布在MP和母细胞之间变化，如通过Western印迹所确定的。这些数据强烈表明，β-肌动蛋白在激动剂诱导的突起形成中起着积极的促进作用，通过与新描述的富含肌动蛋白的结构的机械相互作用。莱瑟姆，S. L.，沙波尼耶角，Dugina，V.，Couraud，P. O.，格劳湾E. R.，Combes，V. β-和γ-细胞质肌动蛋白在内皮微粒形成的机械调节中的合作。FASEB J.27，672-683（2013）。www.fasebj.org
Elevated endothelial microparticle (MP) levels are observed in numerous diseases, increasingly supporting roles as effectors and valuable markers of vascular dysfunction. While a contractile role for the actin cytoskeleton has been implicated in vesiculation, i.e., MP production, the precise interactions and mechanisms of its constituents, beta- and gamma-cytoplasmic actins, is unknown. Human cerebral microvascular endothelial cells were stimulated with known agonists, and vesiculation development was monitored by scanning electron microscopy (SEM) and flow cytometry. These data in combination provide new insight into the kinetics, patterns of vesiculating cell recruitment, and degrees of response specific to stimuli. Reorganization of beta- and gamma-actins, F-actin, vinculin, and talin accompanied significant MP release. beta-Actin redistribution into basal stress fibers following stimulation was associated with increased apically situated actin-rich particulate structures, which in turn directly correlated with electronlucent membrane protrusions observed by SEM. Y-27632 Rho-kinase inhibition abolished basal beta-actin fiber formation, minimizing apically associated actin-rich structures, significantly reducing membrane protrusions and MP release to near basal levels. Cytoskeletal protein expression and distribution varied between MPs and mother cells, as determined by Western blot. These data strongly suggest that beta-actin plays an active facilitative role in agonist-induced protuberance formation, through mechanical interactions with newly described actin-rich structures.-Latham, S. L., Chaponnier, C., Dugina, V., Couraud, P.-O., Grau, G. E. R., Combes, V. Cooperation between beta- and gamma-cytoplasmic actins in the mechanical regulation of endothelial microparticle formation. FASEB J. 27, 672-683 (2013). www.fasebj.org