Physiology and Physiopathology of the Gliovascular Unit Research Group, Center for Interdisciplinary Research in Biology (CIRB), College de France, CNRS Unité Mixte de Recherche 724, INSERM Unité 1050, Labex Memolife, PSL Research University, Paris 75005, France.
Center for Interdisciplinary Research in Biology (CIRB), College de France, Unité Mixte de Recherche 7241 CNRS, Unité1050 INSERM, PSL Research University, Paris 75005, France.
J Cell Sci. 2020 Apr 8;133(7):jcs239756. doi: 10.1242/jcs.239756.
Astrocytes are morphologically complex and use local translation to regulate distal functions. To study the distribution of mRNA in astrocytes, we combined mRNA detection via hybridization with immunostaining of the astrocyte-specific intermediate filament glial fibrillary acidic protein (GFAP). mRNAs at the level of GFAP-immunolabelled astrocyte somata, and large and fine processes were analysed using AstroDot, an ImageJ plug-in and the R package AstroStat. Taking the characterization of mRNAs encoding GFAP-α and GFAP-δ isoforms as a proof of concept, we showed that they mainly localized on GFAP processes. In the APPswe/PS1dE9 mouse model of Alzheimer's disease, the density and distribution of both α and δ forms of mRNA changed as a function of the region of the hippocampus and the astrocyte's proximity to amyloid plaques. To validate our method, we confirmed that the ubiquitous (large subunit ribosomal protein 4) mRNA was present in astrocyte processes as well as in microglia processes immunolabelled for ionized calcium binding adaptor molecule 1 (Iba1; also known as IAF1). In summary, this novel set of tools allows the characterization of mRNA distribution in astrocytes and microglia in physiological or pathological settings.
星形胶质细胞形态复杂，通过局部翻译来调节远端功能。为了研究星形胶质细胞中 mRNA 的分布，我们将通过杂交进行的 mRNA 检测与星形胶质细胞特异性中间丝胶质纤维酸性蛋白 (GFAP) 的免疫染色相结合。使用 AstroDot（ImageJ 的一个插件和 AstroStat R 包）分析了在 GFAP 免疫标记的星形胶质细胞胞体和大、小突起水平上的 mRNA。以编码 GFAP-α 和 GFAP-δ 同工型的 mRNAs 的特征化为概念验证，我们表明它们主要定位于 GFAP 突起上。在阿尔茨海默病的 APPswe/PS1dE9 小鼠模型中，α 和 δ 形式的 mRNA 的密度和分布随海马回区域和星形胶质细胞与淀粉样斑块的接近程度而变化。为了验证我们的方法，我们证实了普遍存在的 (大亚基核糖体蛋白 4) mRNA 存在于星形胶质细胞突起中，以及免疫标记为离子钙结合衔接分子 1 (Iba1；也称为 IAF1) 的小胶质细胞突起中。总之，这组新工具允许在生理或病理条件下对星形胶质细胞和小胶质细胞中 mRNA 分布进行特征描述。
