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Abstract：
Cnaphalocrocis medinalis granulovirus (CnmeGV), belonging to Betabaculovirus cnamedinalis, can infect the rice pest, the rice leaf roller. In 1979, a CnmeGV isolate, CnmeGV-EP, was collected from Enping County, China. In 2014, we collected another CnmeGV isolate, CnmeGV-EPDH3, at the same location and obtained the complete virus genome sequence using Illumina and ONT sequencing technologies. By combining these two virus isolates, we updated the genome annotation of CnmeGV and conducted an in-depth analysis of its genome features. CnmeGV genome contains abundant tandem repeat sequences, and the repeating units in the homologous regions (hrs) exhibit overlapping and nested patterns. The genetic variations within EPDH3 population show the high stability of CnmeGV genome, and tandem repeats are the only region of high genetic variation in CnmeGV genome replication. Some defective viral genomes formed by recombination were found within the population. Comparison analysis of the two virus isolates collected from Enping showed that the proteins encoded by the CnmeGV-specific genes were less conserved relative to the baculovirus core genes. At the genomic level, there are a large number of SNPs and InDels between the two virus isolates, especially in and around the bro genes and hrs. Additionally, we discovered that CnmeGV acquired a segment of non-ORF sequence from its host, which does not provide any new proteins but rather serves as redundant genetic material integrated into the viral genome. Furthermore, we observed that the host\'s transposon piggyBac has inserted into some virus genes. Together, dsDNA viruses could acquire non-coding genetic material from their hosts to expand the size of their genomes. These findings provide new insights into the evolution of dsDNA viruses.
摘要：
地中海夜蛾颗粒病毒（CnmeGV），属于肉芽胞杆状病毒，可以感染水稻害虫，水稻卷叶机.1979年，一个CnmeGV分离株，CnmeGV-EP,是从恩平县收集的，中国。2014年，我们收集了另一种CnmeGV分离株，CnmeGV-EPDH3在同一位置，并使用Illumina和ONT测序技术获得了完整的病毒基因组序列。通过结合这两种病毒分离物，我们更新了CnmeGV的基因组注释,并对其基因组特征进行了深入分析.CnmeGV基因组含有丰富的串联重复序列，并且同源区域中的重复单元(小时)表现出重叠和嵌套模式。EPDH3群体内的遗传变异显示了CnmeGV基因组的高稳定性，和串联重复序列是CnmeGV基因组复制中唯一的高遗传变异区域。在人群中发现了一些通过重组形成的缺陷病毒基因组。从Enping收集的两种病毒分离物的比较分析表明，由CnmeGV特异性基因编码的蛋白质相对于杆状病毒核心基因保守性较低。在基因组层面,两个病毒分离株之间存在大量的SNPs和InDels,特别是在兄弟基因和小时及其周围。此外,我们发现CnmeGV从其宿主获得了一段非ORF序列，它不提供任何新的蛋白质，而是作为整合到病毒基因组中的冗余遗传物质。此外，我们观察到宿主的转座子piggyBac已经插入了一些病毒基因。一起,dsDNA病毒可以从其宿主获得非编码遗传物质以扩大其基因组的大小。这些发现为dsDNA病毒的进化提供了新的见解。
