The dimer initiation sequence stem-loop of human immunodeficiency virus type 1 is dispensable for viral replication in peripheral blood mononuclear cells
The dimer initiation sequence stem-loop of human immunodeficiency virus type 1 is dispensable for viral replication in peripheral blood mononuclear cells
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DOI：
10.1128/jvi.77.15.8329-8335.2003
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发表时间：
2003-08-01
影响因子：
5.4
通讯作者：
Mak, J
中科院分区：
文献类型：
--
作者：
Hill, MK;Shehu-Xhilaga, M;Mak, J
人类免疫缺陷病毒 1 型 (HIV-1) 包含两个基因组 RNA 拷贝，它们通过二聚体起始位点 (DIS) 内的回文序列非共价连接。茎环。与目前使用 T 细胞系的研究得出的 DIS 干或干环对于 HIV-1 感染性至关重要的范式相反，我们在此证明 DIS 干环缺失的 HIV-1 突变体在外周血单核细胞 (PBMC) 中具有复制能力。 DIS 突变体包含野生型 (5'GCGC GC3') 或任意 (5'ACGCGT3') 回文序列代替 39 核苷酸 DIS 茎环（NLCGCGCG 和 NLACGCGT）。这些 DIS 突变体在 SupT1 细胞中存在复制缺陷，这与目前的模型一致，其中 DIS 突变体在 T 细胞系中存在复制缺陷。所有 HIV-1 DIS 突变体在 40 天的感染期内都能够在 PBMC 中复制，并在感染后 40 天保留各自的 DIS 突变。尽管病毒体 RNA 二聚体的稳定性不受 DIS 突变的影响，但与野生型相比，RNA 二聚体表现出分散的迁移特征。在 DIS 突变体中没有发现 Gag 和 GagProPol 前体蛋白的蛋白质加工缺陷。我们的数据提供了直接证据，表明 DIS 干环对于 PBMC 中的病毒复制是可有可无的，并且 HIV-1 复制中 DIS 干环的要求取决于细胞类型。
Human immunodeficiency virus type 1 (HIV-1) contains two copies of genomic RNA that are noncovalently linked via a palindrome sequence within the dimer initiation site (DIS). stem-loop. In contrast to the current paradigm that the DIS stem or stem-loop is critical for HIV-1 infectivity, which arose from studies using T-cell lines, we demonstrate here that HIV-1 mutants with deletions in the DIS stem-loop are replication competent in peripheral blood mononuclear cells (PBMCs). The DIS mutants contained either the wild-type (5'GCGC GC3') or an arbitrary (5'ACGCGT3') palindrome sequence in place of the 39-nucleotide DIS stem-loop (NLCGCGCG and NLACGCGT). These DIS mutants were replication defective in SupT1 cells, concurring with the current model in which DIS mutants are replication defective in T-cell lines. All of the HIV-1 DIS mutants were replication competent in PBMCs over a 40-day infection period and had retained their respective DIS mutations at 40 days postinfection. Although the stability of the virion RNA dimer was not affected by our DIS mutations, the RNA dimers exhibited a diffuse migration profile when compared to the wild type. No defect in protein processing of the Gag and GagProPol precursor proteins was found in the DIS mutants. Our data provide direct evidence that the DIS stem-loop is dispensable for viral replication in PBMCs and that the requirement of the DIS stem-loop in HIV-1 replication is cell type dependent.