The major human immunodeficiency virus type 2 (HIV-2) packaging signal is present on all HIV-2 RNA species: Cotranslational RNA encapsidation and limitation of Gag protein confer specificity
The major human immunodeficiency virus type 2 (HIV-2) packaging signal is present on all HIV-2 RNA species: Cotranslational RNA encapsidation and limitation of Gag protein confer specificity
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DOI：
10.1128/jvi.75.24.12058-12069.2001
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发表时间：
2001-12-01
影响因子：
5.4
通讯作者：
Lever, AML
中科院分区：
文献类型：
--
作者：
Griffin, SDC;Allen, JF;Lever, AML
人类免疫缺陷病毒2型（HIV-2） 5'先导RNA的一个区域的缺失使基因组RNA的封装减少到野生型病毒的5%左右，而病毒蛋白的产生没有缺陷，但严重限制了病毒在Jurkat T细胞中的传播，这表明该区域含有一个主要的顺式作用的封装信号，或psi （psi）。作为主要剪接供体的上游，它存在于所有病毒转录本上。我们已经证明，HIV-2选择其基因组RNA进行共翻译封装，使得野生型HIV-2无法在反式中封装载体RNA。然而，删除psi的病毒封装了HIV-2载体，显示出对Gag蛋白的竞争。HIV-2通过共翻译包装和竞争限制性Gag多蛋白两种新机制克服了包装信号定位特异性的缺乏。
Deletion of a region of the human immunodeficiency virus type 2 (HIV-2) 5' leader RNA reduces genomic RNA encapsidation to about 5% that of wild-type virus with no defect in viral protein production but severely limits virus spread in Jurkat T cells, indicating that this region contains a major cis-acting encapsidation signal, or psi (psi). Being upstream of the major splice donor, it is present on all viral transcripts. We have shown that HIV-2 selects its genomic RNA for encapsidation cotranslationally, rendering wild-type HIV-2 unable to encapsidate vector RNAs in trans. Virus with psi deleted, however, encapsidates an HIV-2 vector, demonstrating competition for Gag protein. HIV-2 overcomes the lack of packaging signal location specificity by two novel mechanisms, cotranslational packaging and competition for limiting Gag polyprotein.