Institute for Hygiene, Westfälische Wilhelms-Universität and University Hospital Münster, Robert Koch-Strasse 41, 48149 Münster, Germany.
Brain Res. 2013 Apr 24;1507:19-27. doi: 10.1016/j.brainres.2013.02.034. Epub 2013 Feb 27.
A hallmark of prion diseases is the accumulation of disease-associated isoforms (PrP(Sc)) which results from the conversion of host-encoded cellular prion proteins (PrP(C)). Using molecular biochemistry, several disease variants of the human Creutzfeldt-Jakob disease have been identified showing several PrP(Sc) variants in individuals and selective accumulation in specific brain regions. As PrP(C) is differentially expressed and post-translationally modified, certain distinct protein compositions may have the ability to convert more efficiently than others. The PrP(C) glycoprotein moiety represents a single yet divers mixture, but little is known about its exact composition. In this study, we separated and characterized PrP(C) derived from six defined human brain regions in regard to their solubility in several detergent solutions and glycoprotein profile formation. We identified four different but regionally distinct protein compositions. PrP(C) found in the neocortex exhibited dominant diglycosylated bands in the high as well as in the low soluble fractions. The proteins in the nucleus lentiformis, thalamus and hippocampus were more soluble with deoxycholic acid as the N-octyl-β-d-glucopyranoside and the diglycosylated bands displayed strong signals in the supernatants and weaker signals in the sediments. Two different protein profiles were established with PrP(C) derived from the medulla oblongata and the solubility of PrP(C) in the cerebellum clearly differed by the choice of detergent. Our findings indicate the existence of several distinct PrP(C) compositions localized in distinct brain regions. Protein variations may be induced by specific modifications to specific regional biological functions.
朊病毒疾病的一个标志是疾病相关异构体（PrP(Sc)）的积累，这是由宿主编码的细胞朊蛋白（PrP(C)）的转化引起的。使用分子生物学，已经鉴定出几种人类克雅氏病的疾病变体，显示个体中有几种 PrP(Sc)变体，并且在特定脑区有选择性积累。由于 PrP(C)表达和翻译后修饰不同，某些特定的蛋白质组成可能具有更高的转化效率。PrP(C)糖蛋白部分代表单一但多样化的混合物，但对其确切组成知之甚少。在这项研究中，我们分离并鉴定了来自六个定义明确的人类大脑区域的 PrP(C)，以了解它们在几种去污剂溶液中的可溶性和糖蛋白谱形成。我们确定了四种不同但具有区域特异性的蛋白质组成。新皮质中的 PrP(C)在高可溶性和低可溶性部分表现出主要的二糖基化带。核豆状核、丘脑和海马中的蛋白质与脱氧胆酸钠一起更易溶解，N-辛基-β-D-吡喃葡萄糖苷和二糖基化带在上清液中显示强信号，在沉淀物中显示弱信号。从延髓和小脑中分离出的 PrP(C)建立了两种不同的蛋白质谱，小脑中 PrP(C)的可溶性因去污剂的选择而明显不同。我们的研究结果表明，在不同的脑区存在几种不同的 PrP(C)组成。蛋白质的变化可能是由特定的修饰引起的，这些修饰针对特定的区域生物学功能。
