Fried G, Han H Q
Department of Molecular and Cellular Neuroscience, Rockefeller University, New York, New York 10021, USA.
Synapse. 1995 May;20(1):44-53. doi: 10.1002/syn.890200108.
We have examined the subcellular distribution of synapsins and synaptophysin in density gradients from synapsin- and vector-transfected NG108-15 cells, since we recently found that transfection of synapsin IIb cDNA into neuroblastoma x glioma hybrid cells (NG108-15) resulted in cell lines that had a more neuronal phenotype than controls. The increase in synapsins and synaptophysin in the transfected cells was maximal in the region of the gradient containing small synaptic vesicles. The transferrin receptor, a marker for early endosomes, did not increase in the synapsin-containing fractions in the transfected cells. Secretogranin I, a soluble protein stored in and secreted from large dense cored vesicles, showed a very pronounced increase in the dense regions of gradients from transfected cells. These subcellular fractionation data suggest a possible role for the synapsins in the regulation of synaptic vesicle function.
我们检测了来自转染突触结合蛋白和载体的NG108-15细胞密度梯度中的突触结合蛋白和突触囊泡蛋白的亚细胞分布，因为我们最近发现，将突触结合蛋白IIb cDNA转染到神经母细胞瘤x胶质瘤杂交细胞（NG108-15）中可产生比对照具有更多神经元表型的细胞系。转染细胞中突触结合蛋白和突触囊泡蛋白的增加在含有小突触囊泡的梯度区域中最大。转铁蛋白受体是早期内体的标志物，在转染细胞中含突触结合蛋白的组分中并未增加。分泌粒蛋白I是一种储存在大致密核心囊泡中并从其分泌的可溶性蛋白质，在转染细胞梯度的致密区域中显示出非常明显的增加。这些亚细胞分级分离数据表明突触结合蛋白在调节突触囊泡功能中可能发挥作用。
