N⁶ methylation of adenosine (m⁶A) was recently discovered to play a role in regulating the life cycle of various viruses by modifying viral and host RNAs. However, different studies on m⁶A effects on the same or different viruses have revealed contradictory roles for m⁶A in the viral life cycle. In this study, we sought to define the role of m⁶A on infection by rice black streaked dwarf virus (RBSDV), a double-stranded RNA virus, of its vector small brown planthopper (SBPH). Infection by RBSDV decreased the level of m⁶A in midgut cells of SBPHs. We then cloned two genes (LsMETTL3 and LsMETTL14) that encode m⁶A RNA methyltransferase in SBPHs. After interference with expression of the two genes, the titre of RBSDV in the midgut cells of SBPHs increased significantly, suggesting that m⁶A levels were negatively correlated with virus replication. More importantly, our results revealed that m⁶A modification might be the epigenetic mechanism that regulates RBSDV replication in its insect vector and maintains a certain virus threshold required for persistent transmission.

中文翻译：

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RNA N6-甲基腺苷修饰抑制水稻黑条矮缩病毒的复制并与病毒在其昆虫载体中的持久性有关

最近发现腺苷的N ^{6甲基化 (m 6} A) 通过修饰病毒和宿主 RNA 在调节各种病毒的生命周期中发挥作用。然而，关于m ⁶ A 对相同或不同病毒影响的不同研究揭示了m ⁶ A 在病毒生命周期中的矛盾作用。在这项研究中，我们试图确定 m ⁶ A 对水稻黑条矮缩病毒 (RBSDV)（一种双链 RNA 病毒）在其载体小褐飞虱 (SBPH) 感染中的作用。RBSDV 感染降低了SBPHs中肠细胞中m ^{6 A 的水平。}然后我们克隆了两个编码 m ^{6的基因（} LsMETTL3和LsMETTL14 ）SBPHs 中的一种 RNA 甲基转移酶。干扰这两个基因的表达后，SBPHs中肠细胞中RBDSV的滴度显着增加，表明m ⁶ A水平与病毒复制呈负相关。更重要的是，我们的研究结果表明，m ⁶ A 修饰可能是调节 RBSDV 在其昆虫载体中复制并维持持续传播所需的一定病毒阈值的表观遗传机制。