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对我国水稻条纹病毒（Rice stripe virus，RSV）北京双桥（RSV-SQ）分离物RNA4片段进行克隆及测序，结果表明RNA4全长为2 157 bp。序列同源性比较发现，在核苷酸水平上，SQ分离物与T、M及CX分离物的vRNA4 ORF同源性分别为98.3 %、98.3 %和96.1 %，vcRNA4 ORF的同源性分别为98.1 %、97.8 %和94.0 %，RNA4 IR的同源性分别为94.8 %、89.4 %和85.4 %；在氨基酸水平上，vRNA4 ORF的同源性分别为100 %、98.9 %和98.9 %，vcRNA4 ORF的同源性均为97.6 %。由此可见，SQ分离物与T分离物的亲缘关系较与M分离物要近，与CX分离物虽同属中国分离物，但其亲缘关系较与日本T、M分离物要远。序列分析同时还发现，这4个分离物5’端非编码区序列完全相同，3’端非编码区只有CX分离物有2个核苷酸发生变化，并且在RNA4 IR上均含有A、U 碱基富集带和反向重复序列，可形成发夹结构。
The RNA4 fragment of RSV-SQ isolates from Rice stripe virus (RSV) in China was cloned and sequenced. The results showed that RNA4 was 2 157 bp in length. Sequence homology comparison showed that at the nucleotide level, the vRNA4 ORF homology between SQ isolates and T, M and CX isolates were 98.3%, 98.3% and 96.1%, respectively. The homologies of vcRNA4 ORFs were The homology of RNA4 IR was 94.8%, 89.4% and 85.4% respectively at 98.1%, 97.8% and 94.0%. At the amino acid level, the homologies of vRNA4 ORF were 100%, 98.9% and 98.9% The homology was 97.6%. Thus, SQ isolates and T isolates were more closely related to the M isolates, while the CX isolates were both isolates from China, but their genetic relationship was more distant from the Japanese T and M isolates. Sequence analysis also showed that the 5 ’untranslated regions of the 4 isolates had the same sequence, and only 2 nucleotides of the CX isolates were changed in the 3’ untranslated region, and both A and U Base-rich bands and inverted repeats form hairpin structures.