Ivell R, Richter D
Brain Res. 1984 Jan 30;292(1):93-8. doi: 10.1016/0006-8993(84)90893-x.
Cell-free translation of rat hypothalamic mRNA and specific immunoprecipitation were used to identify a polypeptide of 16,000 apparent molecular weight as prepro-somatostatin. Quantifying these results suggested that the somatostatin-specific mRNA represented less than 0.01% of the total hypothalamic mRNA. Co-translational addition of microsomal membranes led to the in vitro synthesis of a pro-form of 14,500 molecular weight. By using antisera specifically recognizing 3 different but overlapping segments of somatostatin-28 (SRIF-28), the rat prepro-somatostatin was shown to contain antigenic determinants of this N-terminally extended somatostatin as well as of the tetradecapeptide (SRIF-14). Sequential immunoprecipitation experiments implied the existence of only a single somatostatin precursor among the rat hypothalamic translation products, which would have to be differentially processed to allow release of both SRIF-28 and SRIF-14.
利用大鼠下丘脑信使核糖核酸（mRNA）的无细胞翻译和特异性免疫沉淀法，鉴定出一种表观分子量为16,000的多肽为前促生长抑素原。对这些结果进行定量分析表明，生长抑素特异性mRNA占下丘脑总mRNA的比例不到0.01%。共翻译添加微粒体膜导致体外合成了一种分子量为14,500的前体形式。通过使用特异性识别生长抑素-28（SRIF-28）的3个不同但重叠片段的抗血清，表明大鼠前促生长抑素原含有这种N端延伸的生长抑素以及十四肽（SRIF-14）的抗原决定簇。连续免疫沉淀实验表明，在大鼠下丘脑翻译产物中仅存在单一的生长抑素前体，该前体必须经过差异加工才能释放出SRIF-28和SRIF-14。
