Ahlquist P, Strauss E G, Rice C M, Strauss J H, Haseloff J, Zimmern D
J Virol. 1985 Feb;53(2):536-42. doi: 10.1128/JVI.53.2.536-542.1985.
Although the genetic organization of tobacco mosaic virus (TMV) differs considerably from that of the tripartite viruses (alfalfa mosaic virus [AlMV] and brome mosaic virus [BMV]), all of these RNA plant viruses share three domains of homology among their nonstructural proteins. One such domain, common to the AlMV and BMV 2a proteins and the readthrough portion of TMV p183, is also homologous to the readthrough protein nsP4 of Sindbis virus (Haseloff et al., Proc. Natl. Acad. Sci. U.S.A. 81:4358-4362, 1984). Two more domains are conserved among the AlMV and BMV 1a proteins and TMV p126. We show here that these domains have homology with portions of the Sindbis proteins nsP1 and nsP2, respectively. These results strengthen the view that the four viruses share mechanistic similarities in their replication strategies and may be evolutionarily related. These results also suggest that either the AlMV 1a, BMV 1a, and TMV p126 proteins are multifunctional or Sindbis proteins nsP1 and nsP2 function together as subunits in a single complex.
尽管烟草花叶病毒（TMV）的基因组织与三分体病毒（苜蓿花叶病毒[AlMV]和雀麦花叶病毒[BMV]）有很大不同，但所有这些RNA植物病毒在其非结构蛋白中都有三个同源结构域。其中一个结构域存在于AlMV和BMV的2a蛋白以及TMV p183的通读部分中，它也与辛德毕斯病毒的通读蛋白nsP4同源（哈泽洛夫等人，《美国国家科学院院刊》81:4358 - 4362，1984）。另外两个结构域在AlMV和BMV的1a蛋白以及TMV p126中保守。我们在此表明，这些结构域分别与辛德毕斯病毒蛋白nsP1和nsP2的部分区域具有同源性。这些结果强化了这样一种观点，即这四种病毒在其复制策略上具有机制相似性，并且可能在进化上相关。这些结果还表明，要么AlMV 1a、BMV 1a和TMV p126蛋白具有多种功能，要么辛德毕斯病毒蛋白nsP1和nsP2作为单个复合物中的亚基共同发挥作用。
