The black beetle virus (BBV) is an isometric insect virus whose genome consists of two messenger-active RNA molecules encapsidated in a single virion. The nucleotide sequence of BBV RNA1 (3105 bases) has been determined, and this, together with the sequence of BBV RNA2 (1399 bases) provides the complete primary structure of the BBV genome. The RNA1 sequence encompasses a 5' non-coding region of 38 nucleotides, a coding region for a protein of predicted molecular weight 101,873 (protein A, implicated in viral RNA synthesis) and a 3' proximal region encoding RNA3 (389 bases), a subgenomic messenger RNA made in infected cells but not encapsidated into virions. The RNA3 sequence starts 16 bases inside the coding region of protein A and contains two overlapping open reading frames for proteins of molecular weight 10,760 and 11,633, one of which is believed to be protein B, made in BBV-infected cells. A limited homology exists between the sequences of RNA1 and RNA2. Sequence regions have been identified that provide energetically favorable bonding between RNA2 and RNA1 possibly to facilitate their common encapsidation, and between RNA2 and negative strand RNA1 possibly to regulate the production of RNA3.

中文翻译：

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黑甲虫病毒基因组的结构及其功能含义。

黑甲虫病毒（BBV）是一种等距昆虫病毒，其基因组由包裹在单个病毒粒子中的两个信使活性RNA分子组成。已经确定了BBV RNA1（3105个碱基）的核苷酸序列，并且它与BBV RNA2（1399个碱基）的序列一起提供了BBV基因组的完整一级结构。RNA1序列包含一个38个核苷酸的5'非编码区，一个预测分子量为101,873的蛋白质（蛋白质A，与病毒RNA合成有关）的编码区和一个编码RNA3（389个碱基）的3'近端区。亚基因组信使RNA在受感染的细胞中产生，但没有被病毒颗粒包裹。RNA3序列起始于蛋白质A编码区域内的16个碱基，并包含两个重叠的开放阅读框，分别用于分子量10,760和11,633的蛋白质，据信其中之一是在BBV感染的细胞中产生的B蛋白。RNA1和RNA2的序列之间存在有限的同源性。已经鉴定出在RNA2和RNA1之间提供在能量上有利的键合的序列区域，可能促进它们的共同衣壳化，并且在RNA2和负链RNA1之间提供可能调节RNA3产生的序列上。