Pressure modulation of Ras-membrane interactions and intervesicle transfer.
Pressure modulation of Ras-membrane interactions and intervesicle transfer.
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DOI：
10.1021/ja312671j
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发表时间：
2013-04
影响因子：
15
通讯作者：
S. Kapoor;Alexander Werkmüller;R. Goody;H. Waldmann;R. Winter
中科院分区：
文献类型：
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作者：
S. Kapoor;Alexander Werkmüller;R. Goody;H. Waldmann;R. Winter
附着在质膜上的蛋白质经常会遇到机械应力，包括高静水压(HHP)应力。涉及膜相关小GTP酶(如RAS)的信号通路已被确定为压力扰动的关键基因。然而，机械刺激对生物产出的影响在很大程度上仍然是未知的。本研究通过基于FRET的方法研究了HHP对N-RAS的膜缔合、解离和囊间转移过程的影响，获得了这些过程沿反应路径的动力学参数和体积性质。值得注意的是，膜缔合是在加压的情况下形成的。相反，根据脂膜的性质和侧向组织，可以观察到解离步骤的加速或延迟。此外，HHP可以被推断为N-RAS聚集的正调节因子，特别是在多相膜中。膜相互作用对压力的敏感性提出了脂化信号分子作为机械传感器的作用，通过调节它们的膜结合和解离将机械刺激转换为化学信号。最后，我们的结果首次揭示了压力对生活在极端环境条件下的生物体中与膜相关的RAS控制的信号事件的影响，例如在深海和海底以下环境中遇到的情况，那里的压力达到千巴(100兆帕)范围。
Proteins attached to the plasma membrane frequently encounter mechanical stresses, including high hydrostatic pressure (HHP) stress. Signaling pathways involving membrane-associated small GTPases (e.g., Ras) have been identified as critical loci for pressure perturbation. However, the impact of mechanical stimuli on biological outputs is still largely terra incognita. The present study explores the effect of HHP on the membrane association, dissociation, and intervesicle transfer process of N-Ras by using a FRET-based assay to obtain the kinetic parameters and volumetric properties along the reaction path of these processes. Notably, membrane association is fostered upon pressurization. Conversely, depending on the nature and lateral organization of the lipid membrane, acceleration or retardation is observed for the dissociation step. In addition, HHP can be inferred as a positive regulator of N-Ras clustering, in particular in heterogeneous membranes. The susceptibility of membrane interaction to pressure raises the idea of a role of lipidated signaling molecules as mechanosensors, transducing mechanical stimuli to chemical signals by regulating their membrane binding and dissociation. Finally, our results provide first insights into the influence of pressure on membrane-associated Ras-controlled signaling events in organisms living under extreme environmental conditions such as those that are encountered in the deep sea and sub-seafloor environments, where pressures reach the kilobar (100 MPa) range.