Hantaviruses use the endogenous host factor P58IPK to combat the PKR antiviral response.
Hantaviruses use the endogenous host factor P58IPK to combat the PKR antiviral response.
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DOI：
10.1371/journal.ppat.1010007
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发表时间：
2021-10
期刊：
影响因子：
6.7
通讯作者：
Mir MA
中科院分区：
文献类型：
--
作者：
Wang Z;Ren S;Li Q;Royster AD;Lin L;Liu S;Ganaie SS;Qiu J;Mir S;Mir MA
汉坦病毒核衣壳蛋白（NP）通过一种未知的机制抑制蛋白激酶R（PKR）的二聚化，从而对抗病毒感染时的抗病毒反应。在这里，我们证明了NP利用内源性PKR抑制剂P58 IPK来抑制PKR。P58 IPK的活性通常通过与其负调节因子Hsp 40形成无活性复合物而在细胞中受到限制。另一方面，PKR仍然与40 S核糖体亚基相关，这是一个独特的战略位置，有助于其自由进入下游靶点eIF 2 α。虽然NP和Hsp 40都与P58 IPK结合，但NP的结合亲和力比Hsp 40强得多。P58 IPK具有NP结合位点，跨越N-末端TPR亚结构域I和II。将P58 IPK上的Hsp 40结合位点定位于TPR亚结构域II。NP与P58 IPK的高亲和力结合以及NP与Hsp 40结合位点之间的重叠通过竞争性抑制将P58 IPK从其负调控因子中释放出来。NP-P58 IPK复合物通过NP和核糖体蛋白S19（RPS 19）（40 S核糖体亚基的结构组分）之间的直接相互作用选择性地募集到40 S核糖体亚基。NP对P58 IPK和RPS 19具有不同的结合位点，使其能够充当P58 IPK和40 S核糖体亚基之间的桥梁。与P58 IPK或RPS 19结合缺陷的NP突变体不能抑制PKR，表明P58 IPK与40 S核糖体亚基的选择性接合是PKR抑制所需的。缺乏P58 IPK的细胞产生快速PKR抗病毒应答并建立抗病毒状态，通过整体翻译关闭和病毒载量快速下降观察到。这些研究揭示了一种新的病毒策略，其中NP从其负调控因子中释放P58 IPK，并选择性地将其与40 S核糖体亚基结合，以迅速对抗PKR抗病毒反应。病毒感染期间PKR的激活关闭宿主翻译机器并产生抗病毒状态，从而为病毒蛋白质合成制造障碍。我们的研究结果表明，汉坦病毒劫持内源性PKR抑制剂P58 IPK，以打击PKR的抗病毒反应。PKR仍然与宿主核糖体结合，以获得eIF 2 α的自由进入，从而在病毒感染期间能够迅速关闭宿主翻译装置。本文报道的研究揭示了汉坦病毒NP阻止病毒感染细胞中PKR诱导的宿主翻译关闭的新机制。NP使失活的Hsp 40-P58 IPK复合物解离，并将释放的P58 IPK募集到40 S核糖体亚基，这是PKR的战略位置。P58 IPK的这种策略性募集迅速抑制PKR并防止宿主干扰病毒蛋白合成。
Hantavirus nucleocapsid protein (NP) inhibits protein kinase R (PKR) dimerization by an unknown mechanism to counteract its antiviral responses during virus infection. Here we demonstrate that NP exploits an endogenous PKR inhibitor P58IPK to inhibit PKR. The activity of P58IPK is normally restricted in cells by the formation of an inactive complex with its negative regulator Hsp40. On the other hand, PKR remains associated with the 40S ribosomal subunit, a unique strategic location that facilitates its free access to the downstream target eIF2α. Although both NP and Hsp40 bind to P58IPK, the binding affinity of NP is much stronger compared to Hsp40. P58IPK harbors an NP binding site, spanning to N-terminal TPR subdomains I and II. The Hsp40 binding site on P58IPK was mapped to the TPR subdomain II. The high affinity binding of NP to P58IPK and the overlap between NP and Hsp40 binding sites releases the P58IPK from its negative regulator by competitive inhibition. The NP-P58IPK complex is selectively recruited to the 40S ribosomal subunit by direct interaction between NP and the ribosomal protein S19 (RPS19), a structural component of the 40S ribosomal subunit. NP has distinct binding sites for P58IPK and RPS19, enabling it to serve as bridge between P58IPK and the 40S ribosomal subunit. NP mutants deficient in binding to either P58IPK or RPS19 fail to inhibit PKR, demonstrating that selective engagement of P58IPK to the 40S ribosomal subunit is required for PKR inhibition. Cells deficient in P58IPK mount a rapid PKR antiviral response and establish an antiviral state, observed by global translational shutdown and rapid decline in viral load. These studies reveal a novel viral strategy in which NP releases P58IPK from its negative regulator and selectively engages it on the 40S ribosomal subunit to promptly combat the PKR antiviral responses. Activation of PKR during virus infection shuts down the host translation machinery and creates an antiviral state to create obstacles for viral protein synthesis. Our results demonstrate that hantaviruses hijack an endogenous PKR inhibitor P58IPK to combat the PKR antiviral response. The PKR remains associated with the host ribosomes to gain free access for eIF2α that enables the prompt shutdown of host translation apparatus during virus infection. The studies reported here reveal a novel mechanism by which hantavirus NP prevents PKR induced host translation shutoff in virus infected cells. NP dissociates the inactive Hsp40-P58IPK complex and recruits the released P58IPK to the 40S ribosomal subunit, a strategic PKR location. This tactic recruitment of P58IPK rapidly inhibits PKR and prevents host interference in viral protein synthesis.
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影响因子：
6.7
作者：
Goodman AG;Fornek JL;Medigeshi GR;Perrone LA;Peng X;Dyer MD;Proll SC;Knoblaugh SE;Carter VS;Korth MJ;Nelson JA;Tumpey TM;Katze MG
通讯作者：
Katze MG
DOI：
10.1073/pnas.192298899
发表时间：
2002-10-15
影响因子：
11.1
作者：
Geimonen, E;Neff, S;Mackow, ER
通讯作者：
Mackow, ER
影响因子：
7.2
作者：
Gil, J;Esteban, M
通讯作者：
Esteban, M
影响因子：
5.4
作者：
Alff, Peter J.;Gavrilovskaya, Irina N.;Mackow, Erich R.
通讯作者：
Mackow, Erich R.
影响因子：
4.8
作者：
Melville, MW;Tan, SL;Katze, MG
通讯作者：
Katze, MG