Fabbrini M S, Valsasina B, Nitti G, Benatti L, Vitale A
Istituto Biosintesi Vegetali, Consiglio Nazionale delle Richerche, Milano, Italy.
FEBS Lett. 1991 Jul 29;286(1-2):91-4. doi: 10.1016/0014-5793(91)80948-3.
Synthetic mRNAs were produced using either the complete coding sequence of a human preproendothelin-1 cDNA clone or a truncated form in which the portion encoding the first 17 amino acids, representing a putative signal peptide for insertion into the endoplasmic reticulum, was replaced with a methionine codon. The mRNAs were translated in vitro in the presence or in the absence of microsomal membranes. Protection from trypsin digestion demonstrated that the full-length polypeptide, but not the truncated form, could be inserted into the membranes. Sequence analysis revealed that membrane insertion is accompanied by removal of the first 17 amino acids. These results indicate that the first 17 amino acids of human preproendothelin-1 are a functional signal peptide which allows the protein to enter the secretory pathway.
使用人前内皮素-1 cDNA 克隆的完整编码序列或截短形式来生产合成 mRNA。在截短形式中，编码前 17 个氨基酸（代表插入内质网的假定信号肽）的部分被甲硫氨酸密码子取代。这些 mRNA 在有或无微粒体膜的情况下进行体外翻译。胰蛋白酶消化保护实验表明，全长多肽而非截短形式能够插入膜中。序列分析显示，膜插入伴随着前 17 个氨基酸的去除。这些结果表明，人前内皮素-1 的前 17 个氨基酸是一个功能性信号肽，它使蛋白质能够进入分泌途径。
