Purified integrin adhesion complexes exhibit actin-polymerization activity
Purified integrin adhesion complexes exhibit actin-polymerization activity
复制标题
DOI：
10.1016/j.cub.2005.12.033
复制
发表时间：
2006-02-07
期刊：
影响因子：
9.2
通讯作者：
Blystone, SD
中科院分区：
文献类型：
--
作者：
Butler, B;Gao, CL;Blystone, SD
背景资料：细胞粘附和运动是通过细胞外基质与肌动蛋白细胞骨架经由由整合素受体和相关蛋白组成的粘附复合物的功能性连接来实现的。为了确定这种连接是主动还是被动地实现的，我们从非粘附造血细胞中分离出整合素复合物，并确定它们对actin聚合的影响。结果：我们观察到，α（V）β（3）复合物能够显著加速肌动蛋白组装的速率，导致肌动蛋白纤维在其生长末端被聚集的整合素所束缚。增强肌动蛋白聚合的能力依赖于Arg-Gly-Asp-ligandinduced β（3）酪氨酸磷酸化，激动剂诱导的细胞活化，隔离的透明formins，和clustering of the receptor.Conclusions：这些结果表明，粘附复合物积极促进肌动蛋白组装从他们的胞质面，以建立一个机械连接与细胞外基质。
Background: Cell adhesion and motility are accomplished through a functional linkage of the extracellular matrix with the actin cytoskeleton via adhesion complexes composed of integrin receptors and associated proteins. To determine whether this linkage is attained actively or passively, we isolated integrin complexes from nonadherent hematopoietic cells and determined their influence on the polymerization of actin.Results: We observed that alpha(V)beta(3) complexes are capable of dramatically accelerating the rate of actin assembly, resulting in actin fibers tethered at their growing ends by clustered integrins. The ability to enhance actin polymerization was dependent upon Arg-Gly-Asp-ligandinduced beta(3) tyrosine phosphorylation, agonist-induced cellular activation, sequestration of Diaphanous formins, and clustering of the receptor.Conclusions: These results suggest that adhesion complexes actively promote actin assembly from their cytosolic face in order to establish a mechanical linkage with the extracellular matrix.