Cloning and expression of apolipoprotein B, the major protein of low and very low density lipoproteins.
Cloning and expression of apolipoprotein B, the major protein of low and very low density lipoproteins.
复制标题
低密度脂蛋白和极低密度脂蛋白的主要蛋白载脂蛋白 B 的克隆和表达。
DOI：
10.1073/pnas.82.14.4597
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发表时间：
1985
影响因子：
11.1
通讯作者：
Schotz,MC
中科院分区：
文献类型：
--
作者：
Lusis,AJ;West,R;Mehrabian,M;Reuben,MA;LeBoeuf,RC;Kaptein,JS;Johnson,DF;Schumaker,VN;Yuhasz,MP;Schotz,MC
我们报道了大鼠肝脏载脂蛋白B (apo B) cdna的克隆，并利用克隆序列在mRNA水平上检测载脂蛋白B在大鼠组织中的表达。在lambda gt11表达载体上对大鼠肝脏cDNA文库进行抗体筛选，鉴定出15个载脂蛋白B克隆。融合蛋白产物的免疫学研究证实了克隆的身份。所有克隆似乎都含有仅在载脂蛋白B PI中发现的序列，载脂蛋白B PI是大鼠肝脏载脂蛋白B的高分子量形式。印迹研究表明，克隆杂交到一个20千碱基的肝脏mRNA物种，足以编码整个载脂蛋白B PI肽，估计其大小为400 kDa。载脂蛋白B PI mRNA在肝脏中含量丰富，在肠道中含量较低，但在其他多种组织中均不存在。这种组织分布与体内合成载脂蛋白B的研究结果一致，其中一个克隆对应载脂蛋白B PI mRNA的240个碱基片段，测序发现与大鼠载脂蛋白E mRNA的短区域具有同源性。对相应肽的二级结构的分析没有显示出其他载脂蛋白所具有的两亲性α -螺旋结构的优势。
We report the cloning of cDNAs for rat liver apolipoprotein B (apo B) and the use of the cloned sequences to examine apo B expression at the level of mRNA in rat tissues. Fifteen putative apo B clones were identified by antibody screening of a rat liver cDNA library in the lambda gt11 expression vector. The identity of the clones was confirmed by immunological studies of the fusion protein products. All clones appear to contain sequences found only in apo B PI, the high molecular weight form of rat liver apo B. Blotting studies show that the clones hybridize to a single 20-kilobase liver mRNA species, sufficiently large to encode the entire apo B PI peptide, which is estimated to be 400 kDa in size. Apo B PI mRNA is abundant in liver and present in lower amounts in intestine but is absent in a variety of other tissues examined. This tissue distribution is consistent with that expected from studies on the in vivo synthesis of apo B. One clone, corresponding to a 240-base segment of the apo B PI mRNA, was sequenced and found to exhibit homology with a short region of rat apo E mRNA. Analysis of the secondary structure of the corresponding peptide did not show the preponderance of amphipathic alpha-helical structures characteristic of other apolipoproteins examined thus far.