HIV-1 Tat directly interacts with the interferon-induced, double-stranded RNA-dependent kinase, PKR.
HIV-1 Tat directly interacts with the interferon-induced, double-stranded RNA-dependent kinase, PKR.
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HIV-1 Tat 直接与干扰素诱导的双链 RNA 依赖性激酶 PKR 相互作用。
DOI：
10.1006/viro.1995.0014
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Williams,BR
中科院分区：
文献类型：
--
作者：
McMillan,NA;Chun,RF;Siderovski,DP;Galabru,J;Toone,WM;Samuel,CE;Mak,TW;Hovanessian,AG;Jeang,KT;Williams,BR
我们证明HIV-1达特蛋白和RNA依赖的细胞蛋白激酶PKR在体外和体内都有相互作用，并利用GST融合层析证明PKR与HIV-1达特蛋白直接相互作用。达特中足以结合PKR的区域位于氨基酸20至72内。在体外实验中，两个外显子形式的达特（达特86）被PKR磷酸化，而一个外显子形式的达特（达特72）抑制PKR自身磷酸化和底物磷酸化。在酵母和哺乳动物细胞中均证明了达特与PKR相互作用的能力。PKR在酵母中的表达导致生长抑制表型，该表型被达特的一个外显子形式的共表达逆转。达特72在HeLa细胞中的表达导致与PKR的直接相互作用，如通过与达特抗体的共免疫沉淀所检测的。达特和PKR还在从生产性感染的T淋巴细胞制备的无细胞提取物中形成免疫共沉淀复合物。达特与PKR的相互作用提供了HIV抑制干扰素系统的潜在机制。
We present evidence that the HIV-1 Tat protein and the RNA-dependent cellular protein kinase, PKR, interact with each other bothin vitroandin vivo.Using GST fusion chromatography, we demonstrate that PKR, interacts directly with the HIV-1 Tat protein. The region in Tat sufficient for binding PKR maps within amino acids 20 to 72. Inin vitroassays, the two-exon form of Tat (Tat 86) was phosphorylated by PKR, while the one exon form of Tat (Tat 72) inhibited PKR autophosphorylation and substrate phosphorylation. The ability of Tat to interact with PKR was demonstrated in both yeast and mammalian cells. Expression of PKR in yeast results in a growth suppressor phenotype which was reversed by coexpression of a one exon form of Tat. Expression of Tat 72 in HeLa cells resulted in direct interaction with PKR as detected by coimmunprecipitation with a Tat antibody. Tat and PKR also form a coimmunoprecipitable complex in cell-free extracts prepared from productively infected T lymphocytes. The interaction of Tat with PKR provides a potential mechanism by which HIV could suppress the interferon system.