Ling K S, Zhu H Y, Drong R F, Slightom J L, McFerson J R, Gonsalves D
Department of Plant Pathology, Cornell University, New York State Agricultural Experiment Station, Geneva 14456, USA.
J Gen Virol. 1998 May;79 ( Pt 5):1299-307. doi: 10.1099/0022-1317-79-5-1299.
The RNA genome of grapevine leafroll-associated closterovirus-3 (GLRaV-3) was cloned as a cDNA generated from GLRaV-3-specific dsRNA, and a partial genome sequence of 13154 nucleotides (nt) including the 3' terminus was determined. The sequenced portion contained 13 open reading frames (ORFs) potentially encoding, in the 5'-3' direction, proteins of > 77 kDa (ORF1a; helicase, HEL), 61 kDa (ORF1b; RNA-dependent RNA polymerase, RdRp), 6 kDa (ORF2), 5 kDa (ORF3, small transmembrane protein), 59 kDa (ORF4; heat shock protein 70, HSP70), 55 kDa (ORF5), 35 kDa (ORF6; coat protein, CP), 53 kDa (ORF7; diverged coat protein, CPd), 21 kDa (ORF8), 20 kDa (ORF9), 20 kDa (ORF10), 4 kDa (ORF11), 7 kDa (ORF12), and an untranslated region of 277 nt. ORF1b is probably expressed via a +1 ribosomal frameshift mechanism, most similar to that of lettuce infectious yellows virus (LIYV). Phylogenetic analysis using various gene sequences (HEL, RdRp, HSP70 and CP) clearly demonstrated that GLRaV-3, a mealybug-transmissible closterovirus, is positioned independently from aphid-transmissible monopartite closteroviruses (beet yellows, citrus tristeza and beet yellows stunt) and whitefly-transmissible bipartite closterovirus (lettuce infectious yellows, LIYV). However, another alleged mealybug-transmissible closterovirus, little cherry virus, was shown to be more closely related to the whitefly-transmissible LIYV than to GLRaV-3.
葡萄卷叶相关的长线形病毒3（GLRaV-3）的RNA基因组被克隆为从GLRaV-3特异性双链RNA产生的cDNA，并测定了包括3'末端在内的13154个核苷酸（nt）的部分基因组序列。测序部分包含13个开放阅读框（ORF），可能在5'-3'方向上编码大于77 kDa的蛋白质（ORF1a；解旋酶，HEL）、61 kDa的蛋白质（ORF1b；RNA依赖性RNA聚合酶，RdRp）、6 kDa的蛋白质（ORF2）、5 kDa的蛋白质（ORF3，小跨膜蛋白）、59 kDa的蛋白质（ORF4；热休克蛋白70，HSP70）、55 kDa的蛋白质（ORF5）、35 kDa的蛋白质（ORF6；外壳蛋白，CP）、53 kDa的蛋白质（ORF7；变异外壳蛋白，CPd）、21 kDa的蛋白质（ORF8）、20 kDa的蛋白质（ORF9）、20 kDa的蛋白质（ORF10）、4 kDa的蛋白质（ORF11）、7 kDa的蛋白质（ORF12），以及一个277 nt的非翻译区。ORF1b可能通过+1核糖体移码机制表达，这与莴苣传染性黄化病毒（LIYV）的机制最为相似。使用各种基因序列（HEL、RdRp、HSP70和CP）进行的系统发育分析清楚地表明，GLRaV-3是一种由粉虱传播的长线形病毒，其位置独立于由蚜虫传播的单分体长线形病毒（甜菜黄化病毒、柑橘衰退病毒和甜菜黄化矮化病毒）以及由粉虱传播的双分体长线形病毒（莴苣传染性黄化病毒，LIYV）。然而，另一种据称由粉虱传播的长线形病毒——小樱桃病毒，被证明与由粉虱传播的LIYV的关系比与GLRaV-3的关系更密切。
