A double-stranded RNA platform is required for the interaction between a host restriction factor and the NS1 protein of influenza A virus
A double-stranded RNA platform is required for the interaction between a host restriction factor and the NS1 protein of influenza A virus
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DOI：
10.1093/nar/gkz1094
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发表时间：
2020-01-10
影响因子：
14.9
通讯作者：
Krug, Robert M.
中科院分区：
文献类型：
--
作者：
Chen, Guifang;Ma, Li-Chung;Krug, Robert M.
甲型流感病毒引起广泛的人类呼吸道疾病。病毒多功能NS 1蛋白抑制宿主抗病毒反应。这种抑制作用是由于特异性细胞抗病毒蛋白在NS 1蛋白上不同位置的结合。值得注意的是，几种蛋白质的结合还需要NS 1 N-末端RNA结合结构域（RBD）中的两个氨基酸残基，这是结合双链RNA（dsRNA）所需的。在这里，我们专注于宿主限制性因子DHX 30解旋酶，这是由NS 1蛋白质抗衡，并建立为什么NS 1的dsRNA结合活性是必需的，其结合到DHX 30。我们发现DHX 30的N-末端152个氨基酸残基片段，表示为DHX 30 N，具有DHX 30的所有抗病毒活性，并含有dsRNA结合结构域，并且NS 1-DHX 30在体内的相互作用需要DHX 30 N和NS 1 RBD两者的dsRNA结合活性。我们使用细菌表达的蛋白质证明了为什么会出现这种情况：体外DHX 30 N-NS 1 RBD相互作用需要存在结合NS 1 RBD和DHX 30 N的dsRNA平台。我们提出，类似的双链RNA平台在NS 1蛋白与其他蛋白质的相互作用中发挥作用，这些蛋白质需要NS 1 RBD双链RNA结合活性所需的这两个相同的氨基酸残基。
Influenza A viruses cause widespread human respiratory disease. The viral multifunctional NS1 protein inhibits host antiviral responses. This inhibition results from the binding of specific cellular antiviral proteins at various positions on the NS1 protein. Remarkably, binding of several proteins also requires the two amino-acid residues in the NS1 N-terminal RNA-binding domain (RBD) that are required for binding double-stranded RNA (dsRNA). Here we focus on the host restriction factor DHX30 helicase that is countered by the NS1 protein, and establish why the dsRNA-binding activity of NS1 is required for its binding to DHX30. We show that the N-terminal 152 amino-acid residue segment of DHX30, denoted DHX30N, possesses all the antiviral activity of DHX30 and contains a dsRNA-binding domain, and that the NS1-DHX30 interaction in vivo requires the dsRNA-binding activity of both DHX30N and the NS1 RBD. We demonstrate why this is the case using bacteria-expressed proteins: the DHX30N-NS1 RBD interaction in vitro requires the presence of a dsRNA platform that binds both NS1 RBD and DHX30N. We propose that a similar dsRNA platform functions in interactions of the NS1 protein with other proteins that requires these same two amino-acid residues required for NS1 RBD dsRNA-binding activity.