Cell Dynamics Group, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
Cell Dynamics Group, Max Planck Institute of Biochemistry, 82152 Martinsried, Germany.
Biophys J. 2023 Aug 22;122(16):3386-3394. doi: 10.1016/j.bpj.2023.07.014. Epub 2023 Jul 24.
Circular actin waves that propagate on the substrate-attached membrane of Dictyostelium cells separate two distinct membrane domains from each other: an inner territory rich in phosphatidyl-(3,4,5) trisphosphate (PIP3) and an external area decorated with the PIP3-degrading 3-phosphatase PTEN. During wave propagation, the inner territory increases at the expense of the external area. Beyond a size limit, the inner territory becomes unstable, breaking into an inner and an external domain. The sharp boundary between these domains is demarcated by the insertion of an actin wave. During the conversion of inner territory to external area, the state of the membrane fluctuates, as visualized by dynamic landscapes of formin B binding. Here we analyze the formin B fluctuations in relation to three markers of the membrane state: activated Ras, PIP3, and PTEN.
环形肌动蛋白波在 Dictyostelium 细胞附着于基质的膜上传播，将两个不同的膜域彼此分隔开来：一个富含磷脂酰肌醇-(3,4,5)三磷酸（PIP3）的内部区域和一个用 PIP3 降解 3-磷酸酶 PTEN 装饰的外部区域。在波传播过程中，内部区域会扩大，而外部区域会缩小。当内部区域超过一定大小时，它会变得不稳定，分裂成一个内部和一个外部区域。这些区域之间的锐利边界由肌动蛋白波的插入来划定。在内部区域转化为外部区域的过程中，膜的状态会波动，这可以通过形成素 B 结合的动态景观来可视化。在这里，我们分析了形成素 B 的波动与膜状态的三个标记物之间的关系：激活的 Ras、PIP3 和 PTEN。
