Ho Teerapong, Panyim Sakol, Udomkit Apinunt
Institute of Molecular Biosciences, Mahidol University, Phutthamonthon 4 Road, Salaya, Nahkon Pathom, 73170, Thailand.
Institute of Molecular Biosciences, Mahidol University, Phutthamonthon 4 Road, Salaya, Nahkon Pathom, 73170, Thailand; Department of Biochemistry, Faculty of Science, Mahidol University, Rama VI Road, Bangkok, 10400, Thailand.
Dev Comp Immunol. 2019 Jan;90:130-137. doi: 10.1016/j.dci.2018.09.008. Epub 2018 Sep 15.
Argonaute (Ago) proteins, the catalytic component of an RNA-induced silencing complex (RISC) in RNA interference pathway, function in diverse processes, especially in antiviral defense and transposon regulation. So far, cDNAs encoding four members of Argonaute were found in Penaeus monodon (PmAgo1-4). Two PmAgo proteins, PmAgo1 and PmAgo3 shared high percentage of amino acid identity to Ago1 and Ago2, respectively in other Penaeid shrimps. Therefore, the possible roles of PmAgo1 and PmAgo3 upon viral infection in shrimp were characterized in this study. The level of PmAgo1 mRNA expression in shrimp hemolymph was stimulated upon YHV challenge, but not with dsRNA administration. Interestingly, silencing of either PmAgo1 or PmAgo3 using sequence-specific dsRNAs impaired the efficiency of PmRab7-dsRNA to knockdown shrimp endogenous PmRab7 expression. Inhibition of yellow head virus (YHV) replication and delayed mortality rate were also observed in both PmAgo1-and PmAgo3-knockdown shrimp. In addition, silencing of PmAgo3 transcript, but not PmAgo1, revealed partial inhibition of white spot syndrome virus (WSSV) infection and delayed mortality rate. Therefore, our study provides insights into PmAgo1and PmAgo3 functions that are involved in a dsRNA-mediated gene silencing pathway and play roles in YHV and WSSV replication in the shrimp.
Argonaute（Ago）蛋白是RNA干扰途径中RNA诱导沉默复合体（RISC）的催化成分，在多种过程中发挥作用，尤其是在抗病毒防御和转座子调控方面。到目前为止，在斑节对虾中发现了编码四种Argonaute成员的cDNA（PmAgo1 - 4）。在其他对虾中，两种PmAgo蛋白，即PmAgo1和PmAgo3分别与Ago1和Ago2具有较高的氨基酸同一性百分比。因此，本研究对PmAgo1和PmAgo3在对虾病毒感染后的可能作用进行了表征。对虾血淋巴中PmAgo1 mRNA表达水平在感染黄头病毒（YHV）后受到刺激，但在给予双链RNA（dsRNA）时未受刺激。有趣的是，使用序列特异性dsRNA沉默PmAgo1或PmAgo3会损害PmRab7 - dsRNA敲低对虾内源性PmRab7表达的效率。在敲低PmAgo1和PmAgo3的对虾中还观察到黄头病毒（YHV）复制受到抑制以及死亡率延迟。此外，沉默PmAgo3转录本而非PmAgo1转录本，显示出对白斑综合征病毒（WSSV）感染的部分抑制以及死亡率延迟。因此，我们的研究深入了解了PmAgo1和PmAgo3在dsRNA介导的基因沉默途径中的功能，以及它们在对虾YHV和WSSV复制中所起的作用。
