Jiang T, Liu P, Liao B L, Wu J X, Huang C J
Key Laboratory of Molecular Biology of Crop Pathogens and Insects of MOA, Institute of Biotechnology, Zhejiang University, Hangzhou, P.R. China.
Acta Virol. 2010;54(1):21-6. doi: 10.4149/av_2010_01_21.
Nine samples of diseased Malvastrum coromandelianum plants collected from the fields in Yunnan province of China were found to be infected with Malvastrum yellow vein Yunnan virus (MYVYNV), when tested by PCR using specific primers. The results of PCR and Southern blot analysis showed that only 4 samples out of 9 were associated with the satellite DNAb molecules. Their sequence analysis indicated that DNAb molecules share 97.8%-99.4% of nucleotide sequence identities with DNAb associated with MYVYNV isolate Y160 and less than 82.0% with those associated with other begomoviruses. Two infectious clones of MYVYNV (isolates Y160 and Y277) produced yellow vein, vein thickening and upward leaf curl symptoms in Nicotiana benthamiana plants. In the presence of its cognate DNAb, the symptoms changed to downward leaf curl and crinkle. Southern blot analysis showed that DNAb could increase accumulation of its cognate virus in the infected N. benthamiana plants. The above results indicated that MYVYNV is a monopartite begomovirus and its association with DNAb is not necessary for the infection of plants, but is able to intensify symptoms specific for the disease.
在中国云南省田间采集的9份患病赛葵植株样本，经使用特异性引物进行PCR检测，发现感染了赛葵黄脉云南病毒（MYVYNV）。PCR和Southern杂交分析结果显示，9份样本中只有4份与卫星DNAb分子相关。其序列分析表明，DNAb分子与MYVYNV分离物Y160相关的DNAb核苷酸序列同一性为97.8%-99.4%，与其他双生病毒相关的DNAb核苷酸序列同一性小于82.0%。两个MYVYNV感染性克隆（分离物Y160和Y277）在本氏烟草植株上产生了黄脉、叶脉增厚和叶片向上卷曲症状。在其同源DNAb存在的情况下，症状转变为叶片向下卷曲和皱缩。Southern杂交分析表明，DNAb可增加其同源病毒在被感染的本氏烟草植株中的积累。上述结果表明，MYVYNV是一种单分体双生病毒，其与DNAb的关联对于植物感染并非必需，但能够加重该病的特异性症状。
