Rice tungro, the most important virus disease of rice in South and Southeast Asia, is caused by a complex of two viruses, rice tungro bacilliform virus (RTBV) and rice tungro spherical virus (RTSV). RTBV is a plant pararetrovirus with bacilliform particles, the structure of which is based on T = 3 icosahedral symmetry cut across the threefold axis.The particles encapsidate a circular double-stranded DNA of 8 kbp that encodes four proteins. The current information on the properties, functions, and expression of these proteins is discussed, as is the evidence for replication by reverse transcription. Two major strains of RTBV have been recognized, one from the Indian subcontinent and the other from Southeast Asia. RTSV particles contain a single-stranded RNA genome of 12 kb that encodes a large polyprotein and possibly one or two smaller proteins. The properties and processing of the polyprotein are described and the resemblance to picornaviruses noted.

中文翻译：

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水稻通果病毒的分子生物学。

冬虫夏草是南亚和东南亚最重要的水稻病毒病，是由两种病毒复合而成的，即冬虫夏草杆菌型病毒（RTBV）和冬虫夏草球形病毒（RTSV）。RTBV是一种带有杆菌形颗粒的植物逆转录病毒，其结构基于三倍轴上切开的T = 3二十面体对称性。该颗粒包含8 kbp的环状双链DNA，可编码四种蛋白质。讨论了有关这些蛋白质的性质，功能和表达的当前信息，以及通过逆转录进行复制的证据。已经识别出两种主要的RTBV菌株，一种来自印度次大陆，另一种来自东南亚。RTSV颗粒包含一个12 kb的单链RNA基因组，该基因组编码一种大的多蛋白，可能还编码一种或两种较小的蛋白。