Motiwala Zenia, Sandholu Anand S, Sengupta Durba, Kulkarni Kiran
Division of Biochemical Sciences, CSIR-National Chemical Laboratory, Pune 411008, India.
Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
iScience. 2023 Jun 7;26(7):107031. doi: 10.1016/j.isci.2023.107031. eCollection 2023 Jul 21.
The Ras superfamily of GTPases regulate critical cellular processes by shuttling between GTP-bound ON and GDP-bound OFF states. This switching mechanism is attributed to the conformational changes in two loops, SWI and SWII, upon GTP binding and hydrolysis. Since these conformational changes vary across the Ras superfamily, there is no generic parameter to define their functional states. A unique wavelet coherence (WC) analysis-based approach developed here shows that the structural changes in switch regions could be mapped onto the wavelet coherence phase couplings (WPCs). Thus, WPCs could serve as unique parameters to define their functional states. Disentanglement of WPCs in oncogenic GTPases shows how breakdown of structural allostery leads to their aberrant function. These observations stand out even for simulated ensemble of switch region conformers. Overall, for the first time, we show that WPCs could unravel the latent structural deviations in Ras proteins to decode their universal switching mechanism.
GTP 酶的 Ras 超家族通过在结合 GTP 的活性状态和结合 GDP 的非活性状态之间穿梭来调节关键的细胞过程。这种转换机制归因于 GTP 结合和水解时两个环(SWI 和 SWII)的构象变化。由于这些构象变化在 Ras 超家族中各不相同,因此没有通用参数来定义它们的功能状态。这里开发的一种基于独特小波相干(WC)分析的方法表明,开关区域的结构变化可以映射到小波相干相位耦合(WPC)上。因此,WPC 可以作为定义其功能状态的独特参数。致癌 GTP 酶中 WPC 的解缠表明结构变构的破坏如何导致其异常功能。即使对于开关区域构象异构体的模拟集合,这些观察结果也很突出。总体而言,我们首次表明,WPC 可以揭示 Ras 蛋白中潜在的结构偏差,以解码其通用的转换机制。