Kouassi N K, Chen L, Siré C, Bangratz-Reyser M, Beachy R N, Fauquet C M, Brugidou C
Centre National de Recherche Agronomique (CNRA), Laboratoire Central de Biotechnologies, Abidjan, Côte d'Ivoire.
Arch Virol. 2006 Nov;151(11):2111-22. doi: 10.1007/s00705-006-0802-3. Epub 2006 Jun 19.
The disease caused by rice yellow mottle virus (RYMV) is a major, economically important constraint to rice production in Africa. RYMV is mechanically transmitted by a variety of agents, including insect vectors. The production of resistant rice varieties would be an important advance in the control of the disease and increase rice production in Africa. We produced transgenic plants of the Oryza sativa japonica variety, TP309, to express a RYMV coat protein gene (CP) and mutants of the CP under the control of a ubiquitin promoter. Transgenic plants expressing genes that encode wild-type CP (wt.CP), deleted CP (DeltaNLS.CP), mRNA of the CP, or antisense CP sequences of the CP gene were characterised. Eighty per cent (80%) of independent transgenic lines analysed contained CP gene sequences. Transgenic plants were challenged with RYMV and produced two types of reactions. Most of the plants expressing antisense sequences of the CP and untranslatable CP mRNA exhibited a delay in virus accumulation of up to a week, and the level of virus accumulation was reduced compared with non-transgenic TP309 plants. Transgenic plants expressing RYMV wild-type CP (wt.CP) and deleted CP (DeltaNLS.CP) accumulated the highest levels of virus particles. These results suggest that antisense CP and untranslatable CP mRNA induced moderate resistance, whereas transgenic CP enhanced virus infection.
由水稻黄斑驳病毒（RYMV）引起的疾病是非洲水稻生产的一个主要的、具有重要经济影响的制约因素。RYMV可通过多种媒介进行机械传播，包括昆虫载体。培育抗病水稻品种将是控制该疾病并提高非洲水稻产量的一项重要进展。我们培育了粳稻品种TP309的转基因植株，以在泛素启动子的控制下表达RYMV外壳蛋白基因（CP）及其突变体。对表达编码野生型CP（wt.CP）、缺失CP（DeltaNLS.CP）、CP的mRNA或CP基因反义CP序列的基因的转基因植株进行了表征。分析的独立转基因株系中有80%含有CP基因序列。用RYMV对转基因植株进行攻毒，产生了两种类型的反应。大多数表达CP反义序列和不可翻译CP mRNA的植株在病毒积累方面出现了长达一周的延迟，并且与非转基因TP309植株相比，病毒积累水平有所降低。表达RYMV野生型CP（wt.CP）和缺失CP（DeltaNLS.CP）的转基因植株积累了最高水平的病毒颗粒。这些结果表明，反义CP和不可翻译的CP mRNA诱导了中度抗性，而转基因CP增强了病毒感染。
