Staubach Simon, Müller Stefan, Pekmez Murat, Hanisch Franz-Georg
Institute of Biochemistry II, Medical Faculty, University of Cologne , Joseph-Stelzmann-Str. 52, 50931 Köln, Germany.
Center for Molecular Medicine Cologne, University of Cologne , Robert-Koch-Str. 21, 50931 Köln, Germany.
J Proteome Res. 2017 Feb 3;16(2):516-527. doi: 10.1021/acs.jproteome.6b00658. Epub 2017 Jan 24.
Classical galactosemia, a hereditary metabolic disease caused by the deficiency of galactose-1-phosphate uridyltransferase (GALT; EC 2.7.712), results in an impaired galactose metabolism and serious long-term developmental affection of the CNS and ovaries, potentially related in part to endogenous galactose-induced protein dysglycosylation. In search for galactose-induced changes in membrane raft proteomes of GALT-deficient cells, we performed differential analyses of lipid rafts from patient-derived (Q) and sex- and age-matched control fibroblasts (H) in the presence or absence of the stressor. Label-based proteomics revealed of the total 454 (female) or 678 (male) proteins a proportion of ∼12% in at least one of four relevant ratios as fold-changed. GALT(-) cell-specific effects in the absence of stressor revealed cell-model-dependent affection of biological processes related to protein targeting to the plasma membrane (female) or to cellular migration (male). However, a series of common galactose-induced effects were observed, among them the strongly increased ER-stress marker GRP78 and calreticulin involved in N-glycoprotein quality control. The membrane-anchored N-glycoprotein receptor CD109 was concertedly decreased under galactose-stress together with cadherin-13, GLIPR1, glypican-1, and semaphorin-7A. A series of proteins showed opposite fold-changes in the two cell models, whereas others fluctuated in only one of the two models.
经典型半乳糖血症是一种由1-磷酸半乳糖尿苷转移酶（GALT；EC 2.7.712）缺乏引起的遗传性代谢疾病，会导致半乳糖代谢受损以及中枢神经系统和卵巢出现严重的长期发育问题，这可能部分与内源性半乳糖诱导的蛋白质糖基化异常有关。为了探寻半乳糖对半乳糖-1-磷酸尿苷转移酶缺乏细胞的膜筏蛋白质组的影响，我们对来自患者（Q）以及性别和年龄匹配的对照成纤维细胞（H）的脂筏进行了差异分析，实验条件为存在或不存在应激源。基于标记的蛋白质组学分析显示，在总共454种（女性）或678种（男性）蛋白质中，至少有12%在四个相关比率中的至少一个比率上出现了倍数变化。在无应激源的情况下，GALT（-）细胞特异性效应揭示了与蛋白质靶向质膜（女性）或细胞迁移（男性）相关的生物过程存在细胞模型依赖性影响。然而，我们观察到了一系列常见的半乳糖诱导效应，其中内质网应激标记物GRP78和参与N-糖蛋白质量控制的钙网蛋白显著增加。膜锚定的N-糖蛋白受体CD109在半乳糖应激下与钙黏蛋白-13、GLIPR1、磷脂酰肌醇蛋白聚糖-1和信号素-7A协同下降。一系列蛋白质在两种细胞模型中呈现相反的倍数变化，而其他蛋白质仅在两种模型中的一种中波动。
