Barth Zachary K, Hicklin Ian, Thézé Julien, Takatsuka Jun, Nakai Madoka, Herniou Elisabeth A, Brown Anne M, Aylward Frank O
Department of Biological Sciences, Virginia Tech, 926 West Campus Drive, Blacksburg, VA 24061, USA.
Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA.
Virus Evol. 2024 Jul 12;10(1):veae051. doi: 10.1093/ve/veae051. eCollection 2024.
Polinton-like viruses (PLVs) are a diverse group of small integrative dsDNA viruses that infect diverse eukaryotic hosts. Many PLVs are hypothesized to parasitize viruses in the phylum for their own propagation and spread. Here, we analyze the genomes of novel PLVs associated with the occlusion bodies of entomopoxvirus (EPV) infections of two separate lepidopteran hosts. The presence of these elements within EPV occlusion bodies suggests that they are the first known hyperparasites of poxviruses. We find that these PLVs belong to two distinct lineages that are highly diverged from known PLVs. These PLVs possess mosaic genomes, and some essential genes share homology with mobile genes within EPVs. Based on this homology and observed PLV mosaicism, we propose a mechanism to explain the turnover of PLV replication and integration genes.
类多林顿病毒（PLVs）是一类多样的小型整合双链DNA病毒，可感染多种真核宿主。许多PLVs被推测为为自身繁殖和传播而寄生于该门中的病毒。在此，我们分析了与两种不同鳞翅目宿主的昆虫痘病毒（EPV）感染的包涵体相关的新型PLVs的基因组。这些元件在EPV包涵体内的存在表明它们是已知的首批痘病毒超寄生虫。我们发现这些PLVs属于两个与已知PLVs高度分化的不同谱系。这些PLVs拥有镶嵌基因组，一些必需基因与EPVs中的可移动基因具有同源性。基于这种同源性和观察到的PLV镶嵌现象，我们提出了一种机制来解释PLV复制和整合基因的更替。
