Ribosomal Protein L13 Promotes IRES-Driven Translation of Foot-and-Mouth Disease Virus in a Helicase DDX3-Dependent Manner
Ribosomal Protein L13 Promotes IRES-Driven Translation of Foot-and-Mouth Disease Virus in a Helicase DDX3-Dependent Manner
复制标题
核糖体蛋白 L13 以解旋酶 DDX3 依赖性方式促进 IRES 驱动的口蹄疫病毒翻译
DOI：
10.1128/jvi.01679-19
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发表时间：
2020-01-01
影响因子：
5.4
通讯作者：
Guo, Huichen
中科院分区：
文献类型：
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作者：
Han, Shichong;Sun, Shiqi;Guo, Huichen
内部核糖体进入位点(IRES)驱动的翻译是正向单链RNA病毒绕过宿主细胞5‘端帽子结构要求的常见策略。在目前的研究中，我们发现核糖体蛋白L13(RPL13)是IRES驱动的口蹄疫病毒(FMDV)翻译的关键调节因子，但发现它对细胞全局翻译不是必需的。RPL13也是Seneca Valley病毒(SVV)和猪瘟病毒(CSFV)翻译和感染的决定因素，这表明它的功能也可能在含有IRES的无关病毒中保守。我们进一步表明，死盒解旋酶DDX3的缺失破坏了RPL13与口蹄疫病毒IRES的结合，而RPL13表达的降低削弱了DDX3直接促进IRES驱动的翻译的能力。DDX3与RPL13合作支持80S核糖体的组装，以实现病毒mRNA的最佳翻译起始。最后，我们证明了DDX3影响真核起始因子eIF3亚单位e和j到病毒IRES的募集。这项工作首次在DDX3和eIF3e/j之间建立了联系，并认识到RPL13在调节病毒IRES依赖的翻译中的作用。越来越多的证据揭示了属于60S大亚基的核糖体蛋白(RPS)在调节特定mRNAs选择性翻译中的作用。大亚基RPS在这一过程中的翻译特性是发人深省的，因为它们在催化多肽键的形成中扮演着典型的角色。在这里，我们已经确定核糖体蛋白L13(RPL13)是口蹄疫病毒感染过程中IRES驱动的翻译的关键调节因子。我们的研究支持一种模型，即FMDV IRESS在eIF3e和eIF3j的帮助下，招募识别RPL13的解旋酶DDX3来促进IRES驱动的翻译。更好地了解围绕IRES介导的翻译起始的这些特定相互作用对于选择性翻译病毒mRNA，从而开发有效预防病毒感染的方法具有重要意义。
Internal ribosome entry site (IRES)-driven translation is a common strategy among positive-sense, single-stranded RNA viruses for bypassing the host cell requirement of a 5' cap structure. In the current study, we identified the ribosomal protein L13 (RPL13) as a critical regulator of IRES-driven translation of foot-and-mouth disease virus (FMDV) but found that it is not essential for cellular global translation. RPL13 is also a determinant for translation and infection of Seneca Valley virus (SVV) and classical swine fever virus (CSFV), and this suggests that its function may also be conserved in unrelated IRES-containing viruses. We further showed that depletion of DEAD box helicase DDX3 disrupts binding of RPL13 to the FMDV IRES, whereas the reduction in RPL13 expression impairs the ability of DDX3 to promote IRES-driven translation directly. DDX3 cooperates with RPL13 to support the assembly of 80S ribosomes for optimal translation initiation of viral mRNA. Finally, we demonstrated that DDX3 affects the recruitment of the eukaryotic initiation factor eIF3 subunits e and j to the viral IRES. This work provides the first connection between DDX3 and eIF3e/j and recognition of the role of RPL13 in modulating viral IRES-dependent translation. This previously uncharacterized process may be involved in selective mRNA translation.IMPORTANCE Accumulating evidence has unveiled the roles of ribosomal proteins (RPs) belonging to the large 60S subunit in regulating selective translation of specific mRNAs. The translation speci?city of the large-subunit RPs in this process is thought provoking, given the role they play canonically in catalyzing peptide bond formation. Here, we have identified the ribosomal protein L13 (RPL13) as a critical regulator of IRES-driven translation during FMDV infection. Our study supports a model whereby the FMDV IRESs recruit helicase DDX3 recognizing RPL13 to facilitate IRES-driven translation, with the assistance of eIF3e and eIF3j. A better understanding of these specific interactions surrounding IRES-mediated translation initiation could have important implications for the selective translation of viral mRNA and thus for the development of effective prevention of viral infection.