Dulneva Anna, Lee Sheena, Oliver Peter L, Di Gleria Katalin, Kessler Benedikt M, Davies Kay E, Becker Esther B E
Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK and.
Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK and.
Hum Mol Genet. 2015 Jul 15;24(14):4114-25. doi: 10.1093/hmg/ddv150. Epub 2015 Apr 23.
The Moonwalker (Mwk) mouse is a model of dominantly inherited cerebellar ataxia caused by a gain-of-function mutation in the transient receptor potential (TRP) channel TRPC3. Here, we report impairments in dendritic growth and synapse formation early on during Purkinje cell development in the Mwk cerebellum that are accompanied by alterations in calcium signaling. To elucidate the molecular effector pathways that regulate Purkinje cell dendritic arborization downstream of mutant TRPC3, we employed transcriptomic analysis of developing Purkinje cells isolated by laser-capture microdissection. We identified significant gene and protein expression changes in molecules involved in lipid metabolism. Consistently, lipid homeostasis in the Mwk cerebellum was found to be disturbed, and treatment of organotypic cerebellar slices with ceramide significantly improved dendritic outgrowth of Mwk Purkinje cells. These findings provide the first mechanistic insights into the TRPC3-dependent mechanisms, by which activated calcium signaling is coupled to lipid metabolism and the regulation of Purkinje cell development in the Mwk cerebellum.
“太空漫步者”（Mwk）小鼠是一种由瞬时受体电位（TRP）通道TRPC3功能获得性突变引起的显性遗传性小脑共济失调模型。在此，我们报告了Mwk小鼠小脑中浦肯野细胞发育早期树突生长和突触形成的损伤，同时伴有钙信号的改变。为了阐明在突变型TRPC3下游调节浦肯野细胞树突分支的分子效应途径，我们对通过激光捕获显微切割分离的发育中的浦肯野细胞进行了转录组分析。我们在参与脂质代谢的分子中发现了显著的基因和蛋白质表达变化。一致地，我们发现Mwk小鼠小脑的脂质稳态受到干扰，用神经酰胺处理小脑器官型切片可显著改善Mwk浦肯野细胞的树突生长。这些发现首次为TRPC3依赖性机制提供了机制性见解，通过该机制，激活的钙信号与脂质代谢以及Mwk小鼠小脑中浦肯野细胞发育的调节相耦合。
