Yamamoto A, Yamashiro S, Takamiya K, Atsuta M, Shiku H, Furukawa K
Department of Prosthodontology, School of Dentistry in Nagasaki University, Japan.
J Neurochem. 1995 Dec;65(6):2417-24. doi: 10.1046/j.1471-4159.1995.65062417.x.
Among various tissues of mouse, beta 1,4-N-acetylgalactosaminyltransferase (GM2/GD2 synthase) gene is expressed predominantly in the brain. Further analysis of the gene expression in the mouse CNS was performed by northern blotting and by enzyme assays using extracts from various parts of the CNS. In situ hybridization was also done to investigate the distribution of cells generating GM2/GD2 synthase. In northern blots, diverse levels of the gene expression were observed, depending on the regions examined. By in situ hybridization, pyramidal cells in the hippocampus, granular cells in dentate gyrus and cerebral cortex, Purkinje cells in cerebellum, and mitral cells in the olfactory bulb expressed high levels of the mRNA; these results corresponded to the results obtained by northern blot. Enzyme levels in these sites were accordingly high. However, enzyme levels in certain areas with low mRNA intensities, such as thalamus and pons medulla, were higher than expected from the results of northern blotting. The significance of the high gene expression in certain areas for brain function and the reason for the discrepancy between mRNA level and enzyme activity in some regions are discussed.
在小鼠的各种组织中，β1,4-N-乙酰半乳糖胺基转移酶（GM2/GD2合酶）基因主要在大脑中表达。通过Northern印迹法以及使用来自中枢神经系统不同部位的提取物进行酶活性测定，对小鼠中枢神经系统中的基因表达进行了进一步分析。还进行了原位杂交以研究产生GM2/GD2合酶的细胞分布。在Northern印迹中，根据所检测的区域观察到了不同水平的基因表达。通过原位杂交，海马体中的锥体细胞、齿状回和大脑皮层中的颗粒细胞、小脑中的浦肯野细胞以及嗅球中的二尖瓣细胞表达高水平的mRNA；这些结果与Northern印迹法获得的结果一致。这些部位的酶水平相应较高。然而，某些mRNA强度较低的区域，如丘脑和脑桥延髓，其酶水平高于Northern印迹结果预期。讨论了某些区域中高基因表达对脑功能的意义以及某些区域mRNA水平与酶活性之间差异的原因。
