Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India.
Virus Res. 2010 Sep;152(1-2):19-29. doi: 10.1016/j.virusres.2010.05.015. Epub 2010 Jun 9.
A new tomato-infecting begomovirus and cognate betasatellite were characterized from the gangetic plain of northern India. Genome organization of this virus was found to be similar to those of other old world begomoviruses. The DNA-A molecule (2752nt) shared maximum (85.8%) identity with Tomato leaf curl Laos virus-[Laos] (ToLCLV-[LA]; AF195782) from Laos and betasatellite molecule (1349nt) shared maximum (75.8%) identity with Tomato leaf curl Joydebpur betasatellite (ToLCJoB-[BD:Gaz:05]; AJ966244) from Bangladesh. Interestingly, both these molecules showed less identity with known tomato-infecting begomoviruses and their satellites from India. The recombination detection program (RDP) revealed that these molecules are not an outcome of direct exchange of sequences between existing begomovirus species. According to International Committee on Taxonomy of viruses (ICTV) species/strains demarcations norms for viruses belonging to the family Geminiviridae, this is a new Begomovirus species and we named this virus as Tomato leaf curl Patna virus (ToLCPaV) and new beta species as Tomato leaf curl Patna betasatellite (ToLCPaB). Partial tandem repeats of ToLCPaV and ToLCPaB could induce typical leaf curl symptom on tomato (Solanum lycopersicum) and Nicotiana benthamiana. Although, DNA-A could alone infect tomato typical to a monopartite Begomovirus, co-inoculation of DNA-A and DNA-beta resulted more stunting and severe symptoms. Interestingly, association of ToLCPaB did not assist in increased ToLCPaV accumulation in systemic leaves. ToLCPaV neither transreplicate DNA-B of Tomato leaf curl New Delhi virus (ToLCNDV) nor of Tomato leaf curl Gujarat virus (ToLCGV), presumably due to difference in rep-binding sequences. However, ToLCPaB formed viable pseudorecombinant with mono-bipartite ToLCGV DNA-A infecting both N. benthamiana and tomato but could not cause systemic infection on natural host tomato when co-inoculated with ToLCNDV DNA-A, which is a bipartite Begomovirus.
一种新的侵染番茄的双生病毒及其伴生的 betasatellite 从印度北部的恒河平原被分离出来。该病毒的基因组组织与其他旧世界双生病毒相似。DNA-A 分子（2752nt）与来自老挝的番茄曲叶老挝病毒-[老挝]（ToLCLV-[LA]；AF195782）的同源性最高（85.8%），而 betasatellite 分子（1349nt）与来自孟加拉国的番茄曲叶乔德布尔 betasatellite（ToLCJoB-[BD:Gaz:05]；AJ966244）的同源性最高（75.8%）。有趣的是，这两个分子与来自印度的已知侵染番茄的双生病毒及其卫星的同源性较低。重组检测程序（RDP）显示，这些分子不是现有双生病毒种之间序列直接交换的结果。根据病毒分类国际委员会（ICTV）的种/株划分规范，这是一种新的双生病毒种，我们将该病毒命名为番茄曲叶帕特那病毒（ToLCPaV），新的 beta 种命名为番茄曲叶帕特那 betasatellite（ToLCPaB）。ToLCPaV 和 ToLCPaB 的部分串联重复可以在番茄（Solanum lycopersicum）和 Nicotiana benthamiana 上诱导典型的卷叶症状。尽管 DNA-A 可以单独感染典型的单分体双生病毒，但 DNA-A 和 DNA-beta 的共同接种会导致更严重的矮化和症状。有趣的是，ToLCPaB 的存在并没有促进 ToLCPaV 在系统叶片中的积累。ToLCPaV 既不能复制 Tomato leaf curl New Delhi virus（ToLCNDV）的 DNA-B，也不能复制 Tomato leaf curl Gujarat virus（ToLCGV）的 DNA-B，推测可能是由于 rep-binding 序列的差异。然而，ToLCPaB 与单分体 ToLCGV DNA-A 形成了有活力的假重组，该重组可以侵染 Nicotiana benthamiana 和番茄，但当与 ToLCNDV DNA-A 共同接种时，不能在自然宿主番茄上引起系统感染，而 ToLCNDV DNA-A 是一种二分体双生病毒。
