Hofer L, Weichselbraun I, Quick S, Farrington G K, Böhnlein E, Hauber J
Sandoz Research Institute, Vienna, Austria.
J Virol. 1991 Jun;65(6):3379-83. doi: 10.1128/JVI.65.6.3379-3383.1991.
Expression of the human T-cell leukemia virus type I (HTLV-I) rex gene is a prerequisite for the expression of the retroviral structural proteins. We have generated internal deletion mutants of this 27-kDa nucleolar trans-acting gene product to define functional domains in the Rex protein. The phenotype of the various mutant proteins was tested on the homologous HTLV-I rex response element sequence and the heterologous human immunodeficiency virus type 1 (HIV-1) rev response element sequence. Our results indicate that a region between amino acid residues 55 and 132 in the 189-amino-acid Rex protein is required for Rex-mediated trans activation on both retroviral response element sequences. In addition, substitution of the Rex nuclear localization signal by a sequence of the HIV-1 rev gene product targets the Rex protein to the correct subcellular compartment required for Rex function.
人类I型T细胞白血病病毒（HTLV-I）rex基因的表达是逆转录病毒结构蛋白表达的前提条件。我们构建了这个27 kDa核仁反式作用基因产物的内部缺失突变体，以确定Rex蛋白中的功能结构域。在同源的HTLV-I rex反应元件序列和异源的人类免疫缺陷病毒1型（HIV-1）rev反应元件序列上测试了各种突变蛋白的表型。我们的结果表明，189个氨基酸的Rex蛋白中，氨基酸残基55至132之间的区域对于Rex介导的两种逆转录病毒反应元件序列的反式激活是必需的。此外，用HIV-1 rev基因产物的序列替换Rex核定位信号，可将Rex蛋白靶向到Rex功能所需的正确亚细胞区室。
