Johnson T R, Ilan J
Proc Natl Acad Sci U S A. 1982 Jul;79(13):4088-92. doi: 10.1073/pnas.79.13.4088.
The protein population of poly(A)-containing messenger ribonucleoprotein (mRNP) from cockerel liver was analyzed before and after estradiol induction. Polysomal and free mRNP were isolated by thermal elution from oligo(dT)-cellulose. The proteins were separated by two-dimensional electrophoresis (of which the first dimension was a nonequilibrium pH gradient) and were visualized by silver staining. In order to determine similarities and differences between proteins of various mRNP fractions, trace amounts of 125I-labeled protein from one fraction were coelectrophoresed with stainable amounts of protein from another fraction on the same gel. Of 27 proteins analyzed, 15 were common to polysomal and free mRNP, 7 were specific to polysomal mRNP, and 5 were specific to free mRNP. Moreover, estradiol strongly influenced 11 proteins. Six proteins changed either in relative intensity or in distribution between polysomal and free mRNP fractions. Three major proteins appeared in both fractions, and two additional proteins disappeared from the free mRNP fraction after estradiol treatment. The results suggest that the protein population in polysomal mRNP is quite complex and that the profound influence of estradiol on protein synthesis in cockerel liver may be connected to changes in the protein composition of mRNP.
对公鸡肝脏中含多聚腺苷酸的信使核糖核蛋白（mRNP）的蛋白质群体在雌二醇诱导前后进行了分析。通过从寡聚（dT）纤维素上热洗脱分离多核糖体和游离mRNP。蛋白质通过二维电泳（其中第一维是非平衡pH梯度）进行分离，并通过银染进行可视化。为了确定不同mRNP组分蛋白质之间的异同，将来自一个组分的微量125I标记蛋白质与来自另一个组分的可染色量蛋白质在同一凝胶上进行共电泳。在分析的27种蛋白质中，15种是多核糖体和游离mRNP共有的，7种是多核糖体mRNP特有的，5种是游离mRNP特有的。此外，雌二醇强烈影响11种蛋白质。6种蛋白质在多核糖体和游离mRNP组分之间的相对强度或分布发生了变化。雌二醇处理后，两种组分中出现了三种主要蛋白质，游离mRNP组分中另外两种蛋白质消失。结果表明，多核糖体mRNP中的蛋白质群体相当复杂，雌二醇对公鸡肝脏蛋白质合成的深远影响可能与mRNP蛋白质组成的变化有关。
