Sequential translocation of two phenobarbital-induced polysomal messenger ribonucleic acids from the nuclear envelope to the endoplasmic reticulum.
Sequential translocation of two phenobarbital-induced polysomal messenger ribonucleic acids from the nuclear envelope to the endoplasmic reticulum.
复制标题
两个苯巴比妥诱导的多核糖体信使核糖核酸从核膜到内质网的顺序易位。
DOI：
10.1021/bi00511a034
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发表时间：
1981
期刊：
影响因子：
2.9
通讯作者：
Kasper,CB
中科院分区：
文献类型：
--
作者：
Gonzalez,FJ;Kasper,CB
弗兰克·冈萨雷斯和查尔斯·B·卡斯珀摘要：利用兔网织红细胞蛋白合成系统，结合免疫沉淀和单特异性抗体，对编码环氧化物水合酶和NADPH-细胞色素c氧化还原酶的大鼠肝脏信使核糖核酸(MRNAs)进行了定量。这两种mRNAs的可翻译水平与核膜结合、粗面内质网结合和快速沉淀内质网结合的多聚体有关。在单剂量苯巴比妥后不久，这些mRNAs的可翻译水平在所有三种膜组分中都增加了；然而，增加的速度明显不同。这些mRNAs的激活水平首先出现在核膜结合的多聚体中，然后出现在与粗面内质网结合的多聚体中。在给药后4-6h，两种膜系统的氧化还原酶和环氧化物水合酶mRNAs水平分别达到对照水平的3倍和5倍左右。这些水平随后下降，同时这些mRNAs的可翻译水平增加，内质网迅速沉积，在服用苯巴比妥14-20小时后，内质网达到峰值并稳定在控制值的5倍左右。核包膜水合酶和氧化还原酶在体内合成的增加与其与粗面内质网相关的mRNAs水平密切相关，但与其核被膜mRNAs水平的快速增加无关。然而，这些酶在微体体膜上的体内合成增加，与它们各自的线粒体mRNAs水平的增加密切相关，与内质网迅速下沉有关。这些数据有力地表明，新合成的苯巴比妥诱导的mRNAs首先与核膜和邻近的粗面内质网联系。然后，含有这些mRNAs的多聚体通过粗面内质网转移到内质网的一个区域，该区域具有紧密定位的平行粗糙表面膜阵列的形态特征，在那里信息稳定。核膜由内膜和外膜组成，通过孔道复合体结构连接。包膜的一个独特的结构元素是毛孔复合层，这是一种主要由三种多肽组成的无脂亚组分(Dwyer&Blobel，1976)。这些多肽中的两个之间存在拓扑关系，其中两个显示出广泛的序列同源性(Lam&Kasper，1979)。本文介绍了核仁的理化和生化特征。
Frank J. Gonzalez and Charles B. Kasper* abstract: Quantitation of rat liver messenger ribonucleic acids (mRNAs) coding for epoxide hydratase and NADPH-cytochrome c oxidoreductase was accomplished with a rabbit reticulocyte protein synthesizing system inconjunction with immunoprecipitation with monospecific antibodies. Translatable levels of both mRNAs were found associated with nuclear envelope bound, rough endoplasmic reticulum bound, and rapidly sedimentingendoplasmic reticulum bound poly-somes. Soon after a single dose of phenobarbital, translatable levels of these mRNAs rose in all three membrane fractions; however, the rates of increase were markedly different. Ele-vated levels of these mRNAs first appeared in the nuclear envelope bound polysomes and then in the polysomes bound to the rough endoplasmic reticulum. Maximal levels that were approximately 3-and 5-fold above the control level for oxi-doreductase and epoxide hydratase mRNAs, respectively, were reached for both membrane systems 4-6 h after administration of the drug. These levels then declined concomitantly with an increase in the translatable levels of these mRNAs asso-ciated with rapidly sedimenting endoplasmic reticulum, which peaked and stabilized at a level approximately 5-fold above the control value 14-20 h after administration of pheno-barbital. Increased in vivo synthesis of nuclear envelopeepoxide hydratase and oxidoreductase paralleled closely the levels of their mRNAs associated with the roughendoplasmic re-ticulum but didnot correlate with the rapid increase in their nuclear envelope mRNA levels. The increased synthesis in vivo of these enzymesin the microsomal membrane, however, paralleled closely the increasedlevels of their respective po-lysomal mRNAs associated with rapidly sedimenting endo-plasmic reticulum. These data strongly indicate that newly synthesized phenobarbital-induced mRNAs first become as-sociated with the nuclear envelope and the adjacent rough endoplasmic reticulum. Polysomes containing these mRNAs are then translocated via the rough endoplasmic reticulum to a region of the endoplasmic reticulum morphologically char-acterized by closely positioned parallel arrays of rough-surfaced membrane, where the messages are stabilized. e nuclear envelope is composed of an inner and outer membrane, joined via the pore complex structure. A unique structural element of the envelope is the pore complex lamina, a lipid-free subfraction composed primarily of three poly-peptides (Dwyer & Blobel, 1976). Topologicalinterrela-tionships exist between two of these polypeptides, and two show extensive sequence homology (Lam & Kasper, 1979). The physicochemical and biochemical features of the nuclear en-