Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou Medical University, Guangzhou, Guangdong, China.
Department of Medical Devices, Guangdong Food and Drug Vocational College, Guangzhou, Guangdong, China.
Biosci Rep. 2018 Jul 6;38(4). doi: 10.1042/BSR20180056. Print 2018 Aug 31.
Primary congenital glaucoma (PCG) is an inherited blinding eye disease. The gene was identified as a causal gene for PCG, and many mutations have been found, but no studies have focussed on the molecular epidemiology of in Chinese populations. We aimed to explore the mutation hotspots in Chinese PCG patients and the possible impact of these mutations on the protein structure and function. First, we performed a meta-analysis on seven datasets of Chinese populations and found L107V and R390H to be the most common mutations with allele frequencies of 3.19% and 3.09%, respectively. Then, a series of bioinformatics tools were applied to determine the sequence conservative properties, model the 3D structures, and study the dynamics changes. L107 and R390 are highly conserved residues in close proximity to the hemoglobin-binding region and the active site cavity (ASC), respectively. The mutations changed the distribution of hydrogen bonds and the local electrostatic potential. Long-term molecular dynamics (MD) simulations demonstrated the destabilization of the mutant proteins, especially at the ASC, whose solvent-accessible surface areas (SASAs) were significantly decreased. Compared with the wild-type (WT) protein, the overall structures of the mutants are associated with subtle but significant changes, and the ASC seems to adopt such structures that are not able to perform the WT-like functionality. Therefore, L107V and R390H might be the most important pathogenic mutations in Chinese PCG patients.
原发性先天性青光眼(PCG)是一种遗传性致盲眼病。该基因被确定为 PCG 的致病基因,已经发现了许多突变,但没有研究集中在中国人群中的分子流行病学上。我们旨在探讨中国 PCG 患者中 突变的热点,以及这些突变对蛋白质结构和功能的可能影响。首先,我们对来自中国人群的七个数据集进行了荟萃分析,发现 L107V 和 R390H 是最常见的 突变,等位基因频率分别为 3.19%和 3.09%。然后,应用一系列生物信息学工具来确定序列保守特性、构建 3D 结构,并研究动力学变化。L107 和 R390 是高度保守的残基,分别靠近血红蛋白结合区域和活性位点腔(ASC)。突变改变了氢键的分布和局部静电势。长期的分子动力学(MD)模拟表明,突变蛋白的稳定性降低,特别是在 ASC 处,其溶剂可及表面积(SASAs)显著减小。与野生型(WT)蛋白相比,突变体的整体结构与微妙但显著的变化有关,并且 ASC 似乎采用了无法执行 WT 样功能的结构。因此,L107V 和 R390H 可能是中国 PCG 患者中最重要的致病突变。