Veltman Douwe M
*MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, CB2 0QH, U.K.
Biochem Soc Trans. 2015 Feb;43(1):129-32. doi: 10.1042/BST20140251.
The cytoskeleton is utilized for a variety of cellular processes, including migration, endocytosis and adhesion. The required molecular components are often shared between different processes, but it is not well understood how the cells balance their use. We find that macropinocytosis and cell migration are negatively correlated. Heavy drinkers move only slowly and vice versa, fast cells do not take big gulps. Both processes are balanced by the lipid phosphatidylinositol 3,4,5-trisphosphate (PIP3). Elevated PIP3 signalling causes a shift towards macropinocytosis and inhibits motility by redirecting the SCAR/WAVE complex, a major nucleator of actin filaments. High resolution microscopy shows that patches with high levels of PIP3 recruit SCAR/WAVE on their periphery, resulting in circular ruffle formation and engulfment. Results shed new light on the role of PIP3, which is commonly thought to promote cell motility.
细胞骨架被用于多种细胞过程，包括迁移、胞吞作用和黏附。所需的分子成分通常在不同过程中共享，但细胞如何平衡其使用尚不清楚。我们发现巨胞饮作用和细胞迁移呈负相关。大量进行巨胞饮作用的细胞移动缓慢，反之亦然，移动迅速的细胞不会大口吞噬。这两个过程都由脂质磷脂酰肌醇3,4,5-三磷酸（PIP3）平衡。PIP3信号升高会导致向巨胞饮作用转变，并通过重新引导肌动蛋白丝的主要成核因子SCAR/WAVE复合体来抑制细胞运动。高分辨率显微镜显示，高水平PIP3的斑块在其周边招募SCAR/WAVE，导致形成圆形褶皱并发生吞噬。这些结果为PIP3的作用提供了新的线索，PIP3通常被认为可促进细胞运动。
