Wang Jinbo, Turina Massimo, Medina Vicente, Falk Bryce W
Department of Plant Pathology, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
Virus Res. 2009 Sep;144(1-2):163-70. doi: 10.1016/j.virusres.2009.04.017. Epub 2009 May 4.
Lettuce infectious yellows virus (LIYV), the type member of the genus Crinivirus in the family Closteroviridae, is specifically transmitted by the sweet potato whitefly (Bemisia tabaci) in a semipersistent manner. LIYV infections result in a low virus titer in plants and protoplasts, impeding reverse genetic efforts to analyze LIYV gene/protein functions. We found that synergistic interactions occurred in mixed infections of LIYV and Turnip mosaic virus (TuMV) in Nicotiana benthamiana plants, and these resulted in enhanced accumulation of LIYV. Furthermore, we examined the ability of transgenic plants and protoplasts expressing only the TuMV P1/HC-Pro sequence to enhance the accumulation of LIYV. LIYV RNA and protein titers increased by as much as 8-fold in these plants and protoplasts relative to control plants. LIYV infections remained phloem-limited in P1/HC-Pro transgenic plants, suggesting that enhanced accumulation of LIYV in these plants was due primarily to increased replication efficiency, not to greater spread.
生菜传染性黄化病毒（LIYV）是长线形病毒科毛形病毒属的典型成员，由烟粉虱（Bemisia tabaci）以半持久性方式特异性传播。LIYV感染导致植物和原生质体中的病毒滴度较低，阻碍了分析LIYV基因/蛋白质功能的反向遗传学研究。我们发现，在本氏烟草植株中，LIYV与芜菁花叶病毒（TuMV）混合感染时会发生协同相互作用，这导致LIYV积累增加。此外，我们检测了仅表达TuMV P1/HC-Pro序列的转基因植物和原生质体增强LIYV积累的能力。相对于对照植物，这些植物和原生质体中的LIYV RNA和蛋白质滴度增加了多达8倍。在P1/HC-Pro转基因植物中，LIYV感染仍局限于韧皮部，这表明这些植物中LIYV积累的增加主要是由于复制效率提高，而非传播范围扩大。
