Anti-leprosy drug Clofazimine binds to human Rafl kinase inhibitory protein and enhances ERK phosphorylation  

作　　者：Chenyun Guo Ting Chang Tao Sun Zhihua Wu Yazhuang Dai Hongwei Yao Donghai Lin 

机构地区：[1]Department of Chemical Biology, Key Laboratory for Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China [2]Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China

出　　处：《Acta Biochimica et Biophysica Sinica》2018年第10期1062-1067,共6页生物化学与生物物理学报（英文版）

基　　金：This work was supported by the grants from the Natural Science Foundation of China （Nos. 131470034 and 31670741） and the Fundamental Research Funds for the Central Universities （No. 20720160033）.

摘　　要：Human Rafl kinase inhibitory protein （hRKIP） is an important modulator of the Ras/Rafl/MEK/ERK signaling pathway. Here, we demonstrated that anti-leprosy drug Clofazimine can bind to hRKIP with a significantly stronger affinity than the endogenous substrate phosphatidylethanolamine （PE） by using Biolayer interference technology. Moreover, we identified that residues P74, S75, K80, P111, P112, V177, and P178 play crucial roles in the binding of hRKIP to Clofazimine by using a combination of Nuclear Magnetic Resonance spectroscopy and molecular docking approach. These residues are located at the conserved ligand-binding pocket of hRKIP. Furthermore, we found that 3.2 M Clofazimine could significantly increase the ERK phosphorylation level by about 37%. Our results indicate that Clofazimine can enhance Ras/Rafl/MEK/ERK signaling transduction pathway via binding to hRKIP. This work provides valuable hints for exploiting Clofazimine as a potential lead compound to efficiently treat the diseases related to RKIP or the Ras/Raf/MEK/ERK pathway.Human Rafl kinase inhibitory protein （hRKIP） is an important modulator of the Ras/Rafl/MEK/ERK signaling pathway. Here, we demonstrated that anti-leprosy drug Clofazimine can bind to hRKIP with a significantly stronger affinity than the endogenous substrate phosphatidylethanolamine （PE） by using Biolayer interference technology. Moreover, we identified that residues P74, S75, K80, P111, P112, V177, and P178 play crucial roles in the binding of hRKIP to Clofazimine by using a combination of Nuclear Magnetic Resonance spectroscopy and molecular docking approach. These residues are located at the conserved ligand-binding pocket of hRKIP. Furthermore, we found that 3.2 M Clofazimine could significantly increase the ERK phosphorylation level by about 37%. Our results indicate that Clofazimine can enhance Ras/Rafl/MEK/ERK signaling transduction pathway via binding to hRKIP. This work provides valuable hints for exploiting Clofazimine as a potential lead compound to efficiently treat the diseases related to RKIP or the Ras/Raf/MEK/ERK pathway.

关 键 词：CLOFAZIMINE hRKIP ERK phosphorylation BLI NMR 

分 类 号：Q51[生物学—生物化学] V271.47[航空宇航科学与技术—飞行器设计]