The Rex regulatory protein of human T-cell lymphotropic virus type I binds specifically to its target site within the viral RNA.
The Rex regulatory protein of human T-cell lymphotropic virus type I binds specifically to its target site within the viral RNA.
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人类 T 细胞嗜淋巴细胞病毒 I 型的 Rex 调节蛋白与病毒 RNA 内的靶位点特异性结合。
DOI：
10.1073/pnas.88.16.7145
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发表时间：
1991
影响因子：
11.1
通讯作者：
Pavlakis,GN
中科院分区：
文献类型：
--
作者：
Unge,T;Solomin,L;Mellini,M;Derse,D;Felber,BK;Pavlakis,GN
人t细胞白血病病毒I型（HTLV-I）的Rex蛋白在细菌中表达并得到部分纯化。Rex在体外特异性结合HTLV-I 3'长末端重复序列的RNA序列，称为Rex-responsive element （RXRE）。Rex在体外也能与人类免疫缺陷病毒1型（HIV-1） Rev-responsive element （RRE）结合，而纯化的HIV-1 Rev蛋白不与RXRE结合。因此，在体外获得的结合结果与Rev和Rex在体内的非互反功能一致。Rex特异结合RRE和RXRE，激活HIV-1和HTLV-I的表达，而Rev特异结合RRE，仅激活HIV-1。先前显示缺乏Rev-responsive部分或Rex-responsive部分的Rex与RRE缺失突变体的结合表明，Rex优先与RRE内的不同靶标结合。这些结果表明，像Rev一样，Rex通过结合特定的RNA靶标起作用。
The Rex protein of human T-cell leukemia virus type I (HTLV-I) was expressed in bacteria and partially purified. Rex was shown to bind in vitro specifically to an RNA sequence located in the 3' long terminal repeat of HTLV-I, named Rex-responsive element (RXRE). Rex also bound in vitro to the human immunodeficiency virus type 1 (HIV-1) Rev-responsive element (RRE), while purified HIV-1 Rev protein did not bind to the RXRE. The binding results obtained in vitro are therefore in agreement with the nonreciprocal function of Rev and Rex in vivo. Rex binds specifically to both RRE and RXRE and activates expression in both HIV-1 and HTLV-I, while Rev binds to RRE and activates only HIV-1. Binding of Rex to RRE deletion mutants previously shown to lack either the Rev-responsive or the Rex-responsive portion suggested preferential binding of Rex to a distinct target within the RRE. These results demonstrated that Rex, like Rev, acts by binding to a specific RNA target.