Huang Hung-Jin, Lee Cheng-Chun, Chen Calvin Yu-Chian
Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, College of Pharmacy, China Medical University, Taichung 40402, Taiwan.
School of Medicine, College of Medicine, China Medical University, Taichung 40402, Taiwan.
Biomed Res Int. 2014;2014:764946. doi: 10.1155/2014/764946. Epub 2014 Jun 2.
Deficiency or loss of function of Retinoblastoma-associated proteins (RbAp48) is related with Alzheimer's disease (AD), and AD disease is associated with age-related memory loss. During normal function, RbAp48 forms a complex with the peptide FOG-1 (friend of GATA-1) and has a role in gene transcription, but an unstable complex may affect the function of RbAp48. This study utilizes the world's largest traditional Chinese medicine (TCM) database and virtual screening to provide potential compounds for RbAp48 binding. A molecular dynamics (MD) simulation was employed to understand the variations after protein-ligand interaction. FOG1 was found to exhibit low stability after RbAp48 binding; the peptide displayed significant movement from the initial docking position, a phenomenon which matched the docking results. The protein structure of the other TCM candidates was not variable during MD simulation and had a greater stable affinity for RbAp48 binding than FOG1. Our results reveal that the protein structure does not affect ligand binding, and the top three TCM candidates Bittersweet alkaloid II, Eicosandioic acid, and Perivine might resolve the instability of the RbAp48-FOG1 complex and thus be used in AD therapy.
视网膜母细胞瘤相关蛋白(RbAp48)的功能缺陷或丧失与阿尔茨海默病(AD)相关,且AD与年龄相关的记忆丧失有关。在正常功能中,RbAp48与肽FOG-1(GATA-1之友)形成复合物并在基因转录中起作用,但不稳定的复合物可能会影响RbAp48的功能。本研究利用世界上最大的中药(TCM)数据库和虚拟筛选来提供与RbAp48结合的潜在化合物。采用分子动力学(MD)模拟来了解蛋白质-配体相互作用后的变化。发现FOG1在与RbAp48结合后表现出低稳定性;该肽从初始对接位置有显著移动,这一现象与对接结果相符。在MD模拟过程中,其他中药候选物的蛋白质结构没有变化,并且对RbAp48结合具有比FOG1更高的稳定亲和力。我们的结果表明,蛋白质结构不影响配体结合,排名前三的中药候选物苦味生物碱II、二十碳二酸和佩利文可能解决RbAp48-FOG1复合物的不稳定性,从而用于AD治疗。