Hashimoto J, Koganezawa H
National Institute of Agrobiological Resources, Ibaraki, Japan.
Nucleic Acids Res. 1987 Sep 11;15(17):7045-52. doi: 10.1093/nar/15.17.7045.
The complete nucleotide sequence of apple scar skin viroid(ASSV) has been established, and a probable secondary structure is proposed. A single-stranded circular ASSV RNA consists of 330 nucleotides and can assume the rodlike conformation with extensive base-pairing characteristic of all the known viroids. ASSV shows low sequence homologies with other viroids and lacks the central conserved region. These indicate that ASSV should be allocated to a separate viroid group. However, homologous sequences with potato spindle tuber viroid(PSTV) in ASSV occur in limited and scattered regions of both viroids. These homologous regions fall within the particular domains in the viroid domain model which has been previously proposed by Keese and Symons(Proc. Natl. Acad. Sci. USA. 82, 4582-4586, 1985).
苹果锈果类病毒（ASSV）的完整核苷酸序列已被确定，并提出了一种可能的二级结构。单链环状ASSV RNA由330个核苷酸组成，可呈现出所有已知类病毒特有的具有广泛碱基配对的棒状构象。ASSV与其他类病毒的序列同源性较低，且缺乏中央保守区。这些表明ASSV应被归入一个单独的类病毒组。然而，ASSV中与马铃薯纺锤块茎类病毒（PSTV）的同源序列出现在两种类病毒有限且分散的区域。这些同源区域位于Keese和Symons（《美国国家科学院院刊》82, 4582 - 4586, 1985）先前提出的类病毒结构域模型的特定结构域内。
