Expression of terminin in the rat brain during neuronal differentiation.
Expression of terminin in the rat brain during neuronal differentiation.
复制标题
神经元分化过程中大鼠脑中末端蛋白的表达。
DOI：
10.1016/0006-8993(93)91115-9
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发表时间：
1993
期刊：
影响因子：
2.9
通讯作者：
Wang,E
中科院分区：
文献类型：
--
作者：
Yang,G;Wang,E
终末蛋白是一种细胞质蛋白，最初发现于衰老的培养人成纤维细胞。在本研究中，我们研究了发育过程中的三个大脑区域：大脑皮层，神经视网膜和小脑的大鼠大脑中的终末蛋白的表达。免疫细胞化学结果显示，终末蛋白在脑内主要定位于神经元。在胚胎15天的大脑中，最早观察到对终末蛋白抗体的免疫反应，并且在出生后第一周，大脑皮质中的染色强度达到最高水平，此时大脑神经元进入有丝分裂后，并且它们与靶细胞的突触连接建立。在相同动物的神经视网膜中也观察到类似的终末蛋白发育模式。生物化学表征表明，抗末端蛋白抗体识别90 kDa（TP90）和60 kDa（TP60）多肽的洗涤剂不溶性部分的大鼠大脑的免疫印迹，而TP90被发现在洗涤剂可溶性部分。TP90和TP60多肽出现在胚胎第15天，并在出生后第1天达到最高水平。然而，随着进一步的神经分化的进展，在洗涤剂不溶性部分的TP90减少，并保持在洗涤剂可溶性部分。在洗涤剂不溶性馏分TP60成为主要物种在出生后的第一周。在小脑，其中神经元分化是已知的是相对较晚，定量光密度测量的免疫印迹上的终止蛋白丰度表明，TP60在洗涤剂不溶性部分是在第二周的主要形式。因此，一个占主导地位的TP60的出现与终末神经元分化相一致。Tp60的上调，细胞衰老相关形式的终端，以及可能增加的溶解度的Tp90神经元终末分化发生时，表明终端的表达可能参与调节神经元分化。
Terminin is a cytoplasmic protein originally found in senescent cultured human fibroblasts. In the present study, we investigated terminin expression during development in three brain regions: the cerebral cortex, the neural retina and the cerebellum of the rat brain. By immunocytochemistry we found that terminin immunoreactivity in the brain is mainly localized in neurons. Immunoreactivity to terminin antibody was first noticed in the brain as early as embryonic day 15, and the staining intensity in the cerebral cortex reached maximum level at the first postnatal week, when the cerebral neurons become postmitotic and their synaptic connections with target cells are established. A similar pattern of terminin development was seen in the neural retinas of the same animals as well. Biochemical characterization shows that the anti-terminin antibody recognizes a 90 kDa (Tp90) and a 60 kDa (Tp60) polypeptide in immunoblots of the detergent insoluble fraction of rat brains, while Tp90 was found in the detergent-soluble fraction. Both the Tp90 and Tp60 polypeptides appeared at embryonic day 15 and reached highest levels at postnatal day 1. With the advance of further neural differentiation, however, Tp90 in the detergent-insoluble fraction diminished, and remained only in the detergent-soluble fraction. In the detergent insoluble fraction Tp60 became the predominant species during the first postnatal week. In the cerebellum, where neuronal differentiation is known to be relatively late, quantitative densitometric measurement of terminin abundance on the immunoblots showed that Tp60 in the detergent-insoluble fraction was the predominant form in the second week. Thus, the appearance of a predominant Tp60 coincided with terminal neuronal differentiation. The up-regulation of Tp60, the cell senescence-related form of terminin, as well as a possible increase in solubility of Tp90 when neuronal terminal differentiation takes place, suggest that terminin expression may be involved in the regulation of neuronal differentiation.