Incorporation of Lysyl-tRNA Synthetase into Human Immunodeficiency Virus Type 1

During human immunodeficiency virus type 1 (HIV-1) assembly, tRNA(Lys) isoacceptors are selectively incorporated into virions and tRNA [Formula: see text] is used as the primer for reverse transcription. We show herein that the tRNA(Lys)-binding protein, lysyl-tRNA synthetase (LysRS), is also selectively packaged into HIV-1. The viral precursor protein Pr55(gag) alone will package LysRS into Pr55(gag) particles, independently of tRNA(Lys). With the additional presence of the viral precursor protein Pr160(gag-pol), tRNA(Lys) and LysRS are both packaged into the particle. While the predominant cytoplasmic LysRS has an apparent M(r) of 70,000, viral LysRS associated with tRNA(Lys) packaging is shorter, with an apparent M(r) of 63,000. The truncation occurs independently of viral protease and might be required to facilitate interactions involved in the selective packaging and genomic placement of primer tRNA [Formula: see text].

在人类免疫缺陷病毒1型（HIV-1）的组装过程中，赖氨酸同工接受体转运RNA（tRNA^(Lys) isoacceptors）会被选择性地整合进入病毒粒子，且tRNA₃^Lys被用作反转录的引物。本研究证实，tRNA^(Lys)结合蛋白——赖氨酰-tRNA合成酶（LysRS）同样会被选择性包装进入HIV-1病毒粒子。仅病毒gag前体蛋白Pr55^gag即可独立于tRNA^(Lys)将LysRS包装至Pr55^gag病毒粒子中。当同时存在病毒gag-pol前体蛋白Pr160^gag-pol时，tRNA^(Lys)与LysRS可共同被包装进入病毒粒子。细胞质中主要的LysRS表观分子量为70000，但与tRNA^(Lys)包装相关的病毒LysRS分子量更小，表观分子量为63000。该截短过程不依赖于病毒蛋白酶，且可能是促进引物tRNA₃^Lys选择性包装与基因组定位相关相互作用的必要条件。