Characterization and biosynthesis of the plasma membrane proteolipid protein in neural tissue.
Characterization and biosynthesis of the plasma membrane proteolipid protein in neural tissue.
复制标题
神经组织质膜蛋白脂质蛋白的表征和生物合成。
DOI：
10.1111/j.1471-4159.1986.tb02854.x
复制
发表时间：
1986
影响因子：
4.7
通讯作者：
Sapirstein,VS
中科院分区：
文献类型：
--
作者：
Fischer,I;Sapirstein,VS
在这项研究中，我们表征了脑中质膜蛋白脂质蛋白（PM-PLP）复合物的表达，该复合物可以在脂质双层中形成阳离子选择性通道。我们从突触质膜和神经胶质微粒体中分离出PLP组分，发现其大小和氨基酸组成与我们先前从肾脏中分离出的复合物高度相似。制备了肾脏PM-PLP特异性抗体，并在免疫印迹和免疫沉淀研究的基础上，显示从神经膜分离的PM-PLP复合物与肾脏PM-PLP免疫相关。这些蛋白脂质蛋白质表现出约14 K的分子量，并含有高百分比的疏水性氨基酸与半胱氨酸的明显缺乏。通过在兔网织红细胞裂解物中体外翻译游离和结合的多聚核糖体和总RNA，然后对翻译产物进行免疫沉淀，研究了脑中PM-PLP的生物发生。从这些研究可以得出结论，PM-PLP复合物在粗面内质网上合成。基于从质膜分离的材料和结合的多聚核糖体和分离的RNA翻译后免疫沉淀的材料的相同电泳迁移率，似乎PM-PLP在其合成位点和其掺入质膜之间没有经历可检测的翻译后加工。
In this study we have characterized, in brain, the expression of a plasma membrane proteolipid protein (PM‐PLP) complex that can form cation‐selective channels in lipid bilayers. We isolated PLP fractions from synaptic plasma membrane and glial microsomes and found a high degree of similarity in both size and amino acid composition to the complex we had previously isolated from kidney. Antibodies specific to the kidney PM‐PLP were prepared, and, on the basis of immunoblot and immunoprecipitation studies, the PM‐PLP complex isolated from neural membranes was shown to be immuno‐logically related to the kidney PM‐PLP. These proteolipid proteins exhibited a molecular weight of approximately 14K and contained a high percentage of hydrophobic amino acids with an apparent absence of cysteine. The biogenesis of PM‐PLP in brain was studied by in vitro translation of free and bound polysomes and total RNA in a rabbit reticulocyte lysate followed by immunoprecipitation of the translation products. From these studies it is concluded that the PM‐PLP complex is synthesized on the rough endoplasmic reticulum. On the basis of the identical electrophoretic mobility of material isolated from plasma membranes and material immunoprecipitated after translation of bound polysomes and isolated RNA, it appears that the PM‐PLP does not undergo detectable posttranslational processing between its site of synthesis and its incorporation into the plasma membrane.