RNA Silencing-Mediated Control of <i>Odontoglossum ringspot virus</i>(ORSV) Infection

• 作者: Hongmei Li Nongnong Shi Pengcheng Zhang Xian Zhang Yihua Hu Zhijuan Chen
• 来源期刊: 美国植物学期刊(英文)
• 学科: 医学
• 关键词: ORSV RNA SILENCING AGROINFILTRATION TRANSIENT Expression TRANSGENIC Plant Molecular Analysis
• 年，卷（期）: 2019,（1）
• 页码范围: 147-161
• 页数: 15页
• 分类号: R73

摘要

Odontoglossum ringspot virus (ORSV) infects perennial orchids (Phalaenopsis amabilis) and causes a widespread viral disease. RNA-silencing of viral genes is a promising and effective way of controlling viral infection in plants. An inverted repeat (IR) fragment of the ORSV coat protein gene, cp, was inserted into the pXGY1 vector to generate the silencing construct, pXGY1-ORSV, which was introduced into Nicotiana benthamiana via Agrobacterium-mediated infiltration. A total of 15 homozygous pXGY1-ORSV transgenic N. benthamiana T1 plants were obtained from five transgenic lines, and ORSV cp gene multiplication was reduced by at least 75% - 95% in 12 T2 plants, demonstrating their increased resistance to ORSV. An infectious ORSV clone, pCAMBIA2300-ORSV, was generated to facilitate rigorous analyses of plant viral resistance. Semi-quantitative RT-PCR (sqRT-PCR) and northern-blot analyses revealed that levels of ORSV multiplication and ORSV coat protein were significantly reduced in pXGY1-ORSV transgenic N. benthamiana. Western-blot from pXGY1-ORSV inoculated leaves of ORSV infected P. amabilis also revealed the significant decrease and even degradation of ORSV-CP protein. Disease symptoms were not observed in transgenic plants. These results indicate a high level of ORSV-resistance in pXGY1-ORSV transgenic N. benthamiana.