LOCALIZATION AND SUBCELLULAR-DISTRIBUTION OF CELLULAR RAS GENE-PRODUCTS IN RAT-BRAIN
LOCALIZATION AND SUBCELLULAR-DISTRIBUTION OF CELLULAR RAS GENE-PRODUCTS IN RAT-BRAIN
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DOI：
10.1016/0169-328x(89)90015-6
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发表时间：
1989-01-01
期刊：
影响因子：
--
通讯作者：
TAKAI, Y
中科院分区：
文献类型：
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作者：
MIZOGUCHI, A;UEDA, T;TAKAI, Y
采用单克隆抗体识别Ki-、Ha-和N-ras p21s，利用免疫荧光和免疫印迹技术研究了细胞ras基因产物（c-ras p21s）在大鼠脑中的定位和亚细胞分布。免疫组化分析显示，ras p21s在大脑和小脑皮层的神经堆中表现出较强的免疫反应性。另一方面，神经元核周和白质的免疫反应性较弱，非神经元细胞的免疫反应性未检测到。在大脑亚细胞分离分析中，c-ras p21s主要存在于颗粒组分中，在含有髓磷脂、突触体和线粒体的P2组分中发现了近一半的颗粒结合c-ras p21s，在含有微粒体的P3组分中发现了约三分之一，在含有细胞核和细胞碎片的P1组分中发现了其余的c-ras p21s。在进一步分离P2片段时，大多数c-ras p21s与突触体片段相关。在突触体部分，c-ras p21s在富含突触质膜的部分高度集中，而在富含突触囊泡、突触内线粒体或突触后密度的其他部分则很少存在。计算原匀浆中c-ras p21s的含量为总蛋白的0.05%，c-ras p21s分布在富含突触质膜的部分，比原匀浆富集约4倍。这些结果表明，c-rs p21s主要定位于突触质膜和微粒体，并可能在这些位点参与一些特定的神经元功能。
Localization and subcellular distribution of the cellular ras gene products (c-ras p21s) in rat brain were studied by immunofluorescence and immunoblotting using a monoclonal antibody recognizing all of Ki-, Ha- and N-ras p21s. In immunohistochemical analysis, strong immunoreactivity for ras p21s was observed in the neuropile of cerebral and cerebellar cortex. On the other hand, the immunoreactivity of the neuronal perikarya and that of white matter were weak and that of non-neuronal cells was undetectable. In subcellular fractionation analysis of cerebrum, c-ras p21s were found mostly in the particulate fractions and almost half of the particulate-bound c-ras p21s were recovered in the P2 fraction cotaining myelin, synaptosomes and mitochondria, approximately one-third were in the P3 fraction containing microsomes, and the rest were in the P1 fraction containing nuclei and cell debris. In further fractionation of the P2 fraction, most of c-ras p21s were associated with synaptosomal fraction. In the synaptosomal fraction, c-ras p21s were highly concentrated in the fractions rich in synaptic plasma membranes and were poorly present in the other fractions rich in synapitc vesicles, intrasynaptosomal mitochondria or postsynaptic densities. The content of c-ras p21s of the original homogenate was calculated to be 0.05% of the total protein and c-ras p21s were distributed in the fraction rich in synaptic plasma membranes with approximately 4-fold enrichment over the original homogenate. These results indicate that c-rs p21s are mainly localized in the synaptic plasma membranes and microsomes and suggest that they may participate in some specific neuronal functions at these sites.