Chen Jia-Liang, Su Xun-Cheng
State Key Laboratory of Elemento-organic Chemistry, College of Chemistry, Nankai University, Tianjin, 300071, China.
College of Chemistry, Chemical Engineering and Materials Science, Zaozhuang University, Zaozhuang, 277160, China.
Magn Reson Lett. 2024 Nov 4;5(1):200168. doi: 10.1016/j.mrl.2024.200168. eCollection 2025 Feb.
Rat sarcoma virus oncogene (RAS) proteins are of crucial oncogenic proteins and are involved in several essential intracellular processes. The RAS protein has an intrinsic metal binding site for Mg, which is important for the conformational stability of the active site. Recently, it was reported that a second metal ion binding site, located further from the active site in HRAS (Harvey RAS homolog), binds Ca with millimolar affinity. As one of the most abundant metal ions in cells, Mn is a potential candidate for the second metal ion binding site in RAS proteins. Here, we examined the interaction of Mn with HRAS and KRAS (Kirsten RAS homolog) using high resolution NMR spectroscopy. The NMR data showed that both the second metal ion binding site and the switch I and II regions bind Mn in the RAS proteins. Furthermore, our paramagnetic NMR results disclosed the conformational differences in helix α3 and the following loop between HRAS and KRAS, accompanied by the association with metal ion binding. These results provide new insights into the interaction of RAS proteins and Mn in the respective biological processes in cells.
大鼠肉瘤病毒癌基因（RAS）蛋白是至关重要的致癌蛋白，参与多种重要的细胞内过程。RAS蛋白有一个内在的镁金属结合位点，这对活性位点的构象稳定性很重要。最近有报道称，在HRAS（哈维RAS同源物）中，位于远离活性位点的第二个金属离子结合位点以毫摩尔亲和力结合钙。作为细胞中最丰富的金属离子之一，锰是RAS蛋白中第二个金属离子结合位点的潜在候选者。在这里，我们使用高分辨率核磁共振光谱研究了锰与HRAS和KRAS（柯尔斯顿RAS同源物）的相互作用。核磁共振数据表明，RAS蛋白中的第二个金属离子结合位点以及开关I和II区域都能结合锰。此外，我们的顺磁核磁共振结果揭示了HRAS和KRAS之间α3螺旋及其后的环的构象差异，以及与金属离子结合的相关性。这些结果为细胞中各自生物过程中RAS蛋白与锰的相互作用提供了新的见解。
