Department of Neurology, Emory University, Atlanta, GA, 30322, USA.
Center for Neurodegenerative Diseases, Emory University, Atlanta, GA, 30322, USA.
Nat Commun. 2022 May 25;13(1):2927. doi: 10.1038/s41467-022-30623-x.
Proteomic profiling of brain cell types using isolation-based strategies pose limitations in resolving cellular phenotypes representative of their native state. We describe a mouse line for cell type-specific expression of biotin ligase TurboID, for in vivo biotinylation of proteins. Using adenoviral and transgenic approaches to label neurons, we show robust protein biotinylation in neuronal soma and axons throughout the brain, allowing quantitation of over 2000 neuron-derived proteins spanning synaptic proteins, transporters, ion channels and disease-relevant druggable targets. Next, we contrast Camk2a-neuron and Aldh1l1-astrocyte proteomes and identify brain region-specific proteomic differences within both cell types, some of which might potentially underlie the selective vulnerability to neurological diseases. Leveraging the cellular specificity of proteomic labeling, we apply an antibody-based approach to uncover differences in neuron and astrocyte-derived signaling phospho-proteins and cytokines. This approach will facilitate the characterization of cell-type specific proteomes in a diverse number of tissues under both physiological and pathological states.
使用基于分离策略的脑内细胞类型蛋白质组学分析方法在解析代表其天然状态的细胞表型方面存在局限性。我们描述了一种用于细胞类型特异性表达生物素连接酶 TurboID 的小鼠品系，用于体内蛋白质的生物素标记。通过腺病毒和转基因方法标记神经元，我们在整个大脑的神经元体和轴突中观察到了强大的蛋白质生物素化，从而能够定量分析超过 2000 种神经元衍生的蛋白质，包括突触蛋白、转运蛋白、离子通道和与疾病相关的可成药靶点。接下来，我们对比了 Camk2a-神经元和 Aldh1l1-星形胶质细胞蛋白质组，并在这两种细胞类型中发现了脑区特异性蛋白质组差异，其中一些差异可能潜在地导致对神经疾病的选择性易感性。利用蛋白质组学标记的细胞特异性，我们应用抗体方法来揭示神经元和星形胶质细胞衍生的信号磷酸化蛋白和细胞因子的差异。这种方法将有助于在生理和病理状态下对大量组织中的细胞类型特异性蛋白质组进行特征描述。
