昆虫媒介的翅膀二态是病毒远距离传播和大面积流行的决定因素。尽管植物病毒会影响昆虫媒介的翅膀可塑性,潜在的潜在分子机制很少被研究。这里,我们发现了一种以飞虱为载体的水稻病毒,水稻条纹病毒(RSV),在雄性昆虫中特别诱导长翼形态。对田间种群的分析表明,无论病毒滴度如何,雄性昆虫的长翅比例与RSV感染密切相关。飞虱特异性和睾丸高表达的基因,相遇,偶然发现在RSV诱导的长翼形态中起关键作用。相遇序列类似苹果酸脱氢酶,但它没有相应的酶活性。在幼体早期,相遇被上调以影响雄性翅膀的二态性。作为Akt的下游因子,与胰岛素/胰岛素样生长因子信号通路密切相关,其转录水平响应RSV感染而被激活,导致Encounter的表达升高。此外,RSV衍生的小干扰RNA直接靶向Encounter以增强其表达。我们的研究揭示了一种未报道的机制,该机制是由植物病毒在其昆虫载体中直接调节翅膀二态的,提供了阻断病毒传播的潜在途径。
Wing dimorphism of insect vectors is a determining factor for viral long-distance dispersal and large-area epidemics. Although plant viruses affect the wing plasticity of insect vectors, the potential underlying molecular mechanisms have seldom been investigated. Here, we found that a
planthopper-vectored rice virus, rice stripe virus (RSV), specifically induces a long-winged morph in male insects. The analysis of field populations demonstrated that the long-winged ratios of male insects are closely associated with RSV infection regardless of viral titers. A
planthopper-specific and testis-highly expressed gene, Encounter, was fortuitously found to play a key role in the RSV-induced long-winged morph. Encounter resembles malate dehydrogenase in the sequence, but it does not have corresponding enzymatic activity. Encounter is upregulated to affect male wing dimorphism at early larval stages. Encounter is closely connected with the insulin/insulin-like growth factor signaling pathway as a downstream factor of Akt, of which the transcriptional level is activated in response to RSV infection, resulting in the elevated expression of Encounter. In addition, an RSV-derived small interfering RNA directly targets Encounter to enhance its expression. Our study reveals an unreported mechanism underlying the direct regulation by a plant virus of wing dimorphism in its insect vectors, providing the potential way for interrupting viral dispersal.