Chattopadhyay B, Singh A K, Yadav T, Fauquet C M, Sarin N B, Chakraborty S
Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
Arch Virol. 2008;153(3):533-9. doi: 10.1007/s00705-007-0017-2. Epub 2008 Jan 4.
The full-length genome of a begomovirus and its cognate DNA-beta satellite component associated with chilli leaf curl disease (ChLCD), originating from Varanasi, India, were cloned. Sequence analysis revealed that the viral genome (EF190217) is 2,750 bp and the DNA-beta satellite (EF190215) is 1,361 bp in length. Agroinoculation with partial tandem repeats of the viral genome along with the satellite induced symptoms typical of ChLCD in chilli and Nicotiana benthamiana. However, symptom expression was delayed and milder when the viral genome was agroinoculated alone in these hosts. Sequence comparisons revealed that the genome had the highest sequence identity (95%) with that of chilli leaf curl virus-PK[PK:Mul:98]. The DNA-beta satellite shared maximum sequence identity (88%) with a DNA-beta satellite associated with tomato leaf curl disease from Rajasthan (ToLCBDB-[IN:Raj:03]). These results demonstrate that ChLCD is caused by a complex consisting of the monopartite chilli leaf curl virus and a DNA-beta satellite component. This is the first experimental demonstration of Koch's postulates using cloned DNA molecules associated with chilli leaf curl disease.
克隆了源自印度瓦拉纳西、与辣椒卷叶病（ChLCD）相关的双生病毒全长基因组及其同源DNA-β卫星组分。序列分析显示，病毒基因组（EF190217）长度为2750 bp，DNA-β卫星（EF190215）长度为1361 bp。用病毒基因组的部分串联重复序列与卫星一起进行农杆菌接种，在辣椒和本氏烟草中诱发了典型的ChLCD症状。然而，当病毒基因组单独在这些寄主中进行农杆菌接种时，症状表现延迟且较轻。序列比较显示，该基因组与辣椒卷叶病毒-PK[PK:Mul:98]的基因组具有最高的序列同一性（95%）。DNA-β卫星与来自拉贾斯坦邦的与番茄卷叶病相关的DNA-β卫星（ToLCBDB-[IN:Raj:03]）具有最大的序列同一性（88%）。这些结果表明，ChLCD是由单分体辣椒卷叶病毒和DNA-β卫星组分组成的复合体引起的。这是首次使用与辣椒卷叶病相关的克隆DNA分子对科赫法则进行的实验证明。
