Abstract：
Plasma membranes (PMs) are highly dynamic structures where lipids and proteins can theoretically diffuse freely. However, reports indicate that PM proteins do not freely diffuse within their planes but are constrained by cytoskeleton networks, though the mechanisms for how the cytoskeleton restricts lateral diffusion of plant PM proteins are unclear. Through single-molecule tracking, we investigated the dynamics of six Arabidopsis (Arabidopsis thaliana) PM proteins with diverse structures and found distinctions in sizes and dynamics among these proteins. Moreover, we showed that the cytoskeleton, particularly microtubules, limits the diffusion of PM proteins, including transmembrane and membrane-anchoring proteins. Interestingly, the microfilament skeleton regulates intracellular transport of endocytic cargo. Therefore, these findings indicate that the cytoskeleton controls signal transduction by limiting diffusion of PM proteins in specific membrane compartments and participating in transport of internalized cargo vesicles, thus actively regulating plant signal transduction.
摘要：
质膜（PM）是高度动态的结构，脂质和蛋白质理论上可以自由扩散。然而,报告表明PM蛋白在其平面内不能自由扩散，但受到细胞骨架网络的约束，尽管细胞骨架如何限制植物PM蛋白的横向扩散的机制尚不清楚。通过单分子追踪,我们研究了六种具有不同结构的拟南芥（拟南芥）PM蛋白的动力学，并发现了这些蛋白在大小和动力学上的差异。此外，我们发现细胞骨架,特别是微管，限制PM蛋白的扩散，包括跨膜和膜锚定蛋白。有趣的是,微丝骨架调节胞吞货物的细胞内运输。因此,这些发现表明，细胞骨架通过限制PM蛋白在特定膜区室中的扩散和参与内化货物囊泡的运输来控制信号转导，从而积极调控植物的信号转导。
