Brachmann C B, Boeke J D
Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
J Virol. 1997 Jan;71(1):812-7. doi: 10.1128/JVI.71.1.812-817.1997.
The two-hybrid system was used to define regions of the Ty1 Gag protein responsible for multimerization. Gag truncations lacking the first 146 or the last 97 amino acids (Gag is 440 amino acids in length) interact. A severely C-terminally truncated molecule (lacking the last 207 amino acids) was the smallest truncation to interact, suggesting that some protein-protein interactions between Gag molecules are mediated through the first 233 amino acids. However, an internal deletion of amino acids 147 to 233 does not abolish Gag-Gag interaction, indicating that more than one region can mediate Gag interaction. Surprisingly, we found that a truncation lacking the last 97 amino acids interacts with itself but not with full-length Gag. This is apparently due to an artifact of the two-hybrid assay, since these same molecules coassemble with wild-type Gag into Ty1 virus-like particles.
双杂交系统用于确定负责多聚化的Ty1 Gag蛋白区域。缺少前146个或后97个氨基酸（Gag全长440个氨基酸）的Gag截短体相互作用。一个严重截短C末端的分子（缺少最后207个氨基酸）是能相互作用的最小截短体，这表明Gag分子之间的一些蛋白质-蛋白质相互作用是通过前233个氨基酸介导的。然而，147至233位氨基酸的内部缺失并不消除Gag-Gag相互作用，这表明不止一个区域可以介导Gag相互作用。令人惊讶的是，我们发现缺少最后97个氨基酸的截短体与自身相互作用，但不与全长Gag相互作用。这显然是由于双杂交检测的假象，因为这些相同的分子与野生型Gag共同组装成Ty1病毒样颗粒。
