A 38,000-DALTON MEMBRANE-PROTEIN (P38) PRESENT IN SYNAPTIC VESICLES
A 38,000-DALTON MEMBRANE-PROTEIN (P38) PRESENT IN SYNAPTIC VESICLES
复制标题
DOI：
10.1073/pnas.82.12.4137
复制
发表时间：
1985-01-01
影响因子：
11.1
通讯作者：
GREENGARD, P
中科院分区：
文献类型：
--
作者：
JAHN, R;SCHIEBLER, W;GREENGARD, P
在大鼠大脑的突触小泡中发现了一种表观分子量为 38,000 道尔顿的蛋白质，称为 p38。 p38 的亚细胞分布及其一些特性是借助多克隆和单克隆抗体测定的。 p38 的亚细胞分布与突触小泡特异性磷蛋白突触蛋白 I 的亚细胞分布相似。通过控制孔径玻璃珠色谱纯化的突触小泡部分中的 p38 显示出比粗匀浆富集了 20 倍以上。对不同大脑区域切片的免疫染色显示，大多数（甚至可能是全部）神经末梢都有强烈的标记。仅在高尔基体区域观察到微弱的反应，并且没有观察到轴突和树突的可检测标记。二维电泳显示 p38 具有酸性 pI [等电点]。溶解实验以及使用 Triton X-114 的相分离实验表明 p38 是一种完整的膜蛋白。抗体与完整突触小泡的结合，以及完整和去污剂处理的小泡的受控蛋白水解消化，揭示了 p38 具有暴露在细胞质表面上的结构域。
A protein with an apparent molecular mass of 38,000 daltons designated p38 was found in synaptic vesicles from rat brain. The subcellular distribution of p38 and some of its properties were determined with the aid of polyclonal and monoclonal antibodies. The subcellular distribution of p38 was similar to that of synapsin I, a synaptic-vesicle specific phosphoprotein. p38 in the synaptic vesicle fraction purified by controlled-pore glass bead chromatography showed an enrichment of more than 20-fold over the crude homogenate. Immunostaining of sections through various brain regions revealed an intense labeling of most, and possibly all, nerve terminals. Only faint reactions in the region of the Golgi apparatus and no detectable labeling of axons and dendrites was observed. Two-dimensional electrophoresis revealed that p38 has an acidic pI [isoelectric point]. Solubilization experiments, as well as phase separation experiments using Triton X-114, indicated that p38 is an integral membrane protein. Binding of antibodies to intact synaptic vesicles, as well as controlled proteolytic digestion of intact and detergent-treated vesicles, revealed that p38 has a domain exposed on the cytoplasmic surface.