1 Center for Systems Biology and Molecular Medicine, Yenepoya Research Centre, Yenepoya (Deemed to be University) , Mangalore, India .
2 Department of Ophthalmology, Yenepoya Medical College, Yenepoya (Deemed to be University) , Mangalore, India .
OMICS. 2018 Oct;22(10):642-652. doi: 10.1089/omi.2018.0130.
Ophthalmology and visual health are new frontiers for postgenomic research and technologies such as proteomics. In this context, the optic nerve and retina extend as the outgrowth of the brain, wherein the latter receives the optical input and the former relays the information for processing. While efforts to understand the optic nerve proteome have been made earlier, there exists a lacuna in its biochemical composition and molecular functions. We report, in this study, a high-resolution mass spectrometry-based approach using an Orbitrap Fusion Tribrid mass spectrometer to elucidate the human optic nerve proteomic profile. Raw spectra were searched against NCBI Human RefSeq 75 database using SEQUEST HT and MASCOT algorithms. We identified nearly 35,000 peptides in human optic nerve samples, corresponding to 5682 proteins, of which 3222 proteins are being reported for the first time. Label-free quantification using spectral abundance pointed out to neuronal structural proteins such as myelin basic protein, glial fibrillary acidic protein, and proteolipid protein 1 as the most abundant proteins. We also identified several neurotransmitter receptors and postsynaptic density synaptosomal scaffold proteins. Pathway analysis revealed that a majority of the proteins are structural proteins and have catalytic and binding activity. This study is one of the largest proteomic profiles of the human optic nerve and offers the research community an initial baseline optic nerve proteome for further studies. This will also help understand the protein dynamics of the human optic nerve under normal conditions.
眼科和视觉健康是后基因组研究和蛋白质组学等技术的新前沿。在这种情况下，视神经和视网膜延伸为大脑的外生组织，其中后者接收光输入，前者传递用于处理的信息。虽然早期已经有努力来了解视神经蛋白质组，但它的生化组成和分子功能仍存在空白。我们在本研究中报告了一种基于高分辨率质谱的方法，使用 Orbitrap Fusion Tribrid 质谱仪来阐明人类视神经蛋白质组学图谱。使用 SEQUEST HT 和 MASCOT 算法，将原始光谱与 NCBI 人类 RefSeq 75 数据库进行搜索。我们在人类视神经样本中鉴定出近 35000 种肽，对应 5682 种蛋白质，其中 3222 种蛋白质是首次报道的。使用光谱丰度进行的无标记定量指出，神经元结构蛋白，如髓鞘碱性蛋白、神经胶质纤维酸性蛋白和蛋白脂质蛋白 1，是最丰富的蛋白质。我们还鉴定了几种神经递质受体和突触后密度突触小体支架蛋白。途径分析表明，大多数蛋白质是结构蛋白，具有催化和结合活性。这项研究是人类视神经最大的蛋白质组学图谱之一，为研究人员提供了人类视神经蛋白质组的初始基线，以进行进一步的研究。这也将有助于了解人类视神经在正常条件下的蛋白质动态。
