A Novel Route Controlling Begomovirus Resistance by the Messenger RNA Surveillance Factor Pelota.
A Novel Route Controlling Begomovirus Resistance by the Messenger RNA Surveillance Factor Pelota.
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DOI：
10.1371/journal.pgen.1005538
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发表时间：
2015-10
期刊：
影响因子：
4.5
通讯作者：
Levin I
中科院分区：
文献类型：
--
作者：
Lapidot M;Karniel U;Gelbart D;Fogel D;Evenor D;Kutsher Y;Makhbash Z;Nahon S;Shlomo H;Chen L;Reuveni M;Levin I
番茄黄化曲叶病毒（Tomato yellow leaf curl virus，TYLCV）是番茄的一种毁灭性病害，利用抗病品种可以有效地防治TYLCV。TYLCV抗性系TY 172在第4号染色体上携带TYLCV抗性的主要隐性基因座，命名为ty-5。在这项研究中，27个多态性DNA标记之间的关联，跨越ty-5位点，和接种TYLCV在51个分离的重组群体的单株的抗性特性进行了分析。这些分析将ty-5定位到包含两个颠换的425 bp区域中：一个在编码信使RNA监视因子Pelota（Pelo）的番茄同源物的基因的第一外显子中，第二个在其近端启动子中。对感病和抗病株系的分析表明，无论植株是否感染TYLCV，该基因的相对转录水平保持不变。这表明在该基因编码区发现的多态性控制了抗性。感病株系中Pelo基因的沉默使转基因植株高度抗病，而抗病株系TY 172中Pelo基因的沉默对症状发展没有影响。此外，该基因的感病等位基因在抗性TY 172系中的过表达使其感病，而抗性等位基因在感病植株中的过表达没有影响。这些结果证实Pelo是ty-5基因座上控制抗性的基因。Pelo涉及蛋白质合成的核糖体再循环阶段，提供了一种替代途径来促进对TYLCV和其他病毒的抗性。番茄是世界上最重要的粮食作物之一，为我们的饮食提供植物营养素和颜色。番茄黄化曲叶病毒（Tomato yellow leaf curl virus，TYLCV）是番茄生产中最具毁灭性的病毒之一，也是主要番茄产区番茄生产的主要限制因子。TYLCV的管理是困难的，因为其粉虱媒介种群可以达到很高的数量，并在很大程度上依赖于危险化学品（杀虫剂）的应用。培育抗TYLCV的番茄品种提供了一个有吸引力的，环境友好的策略，以减少由病毒造成的产量损失。在培育抗TYLCV番茄品种方面已经投入了相当大的努力。发现和利用控制抗性的基因可以加快育种进程，并突出了促进这种抗性的先天手段。在这里，我们报告的基因控制TYLCV抗性的ty-5位点的发现。发现信使RNA监视因子Pelo负责这种抗性。我们的发现，连同最近发现的控制抗性的基因在Ty-1/Ty-3基因座，可以导致这两个基因的精确测序，以提高番茄植物对TYLCV的抗性谱，并可能对其他菜豆花叶病毒。
Tomato yellow leaf curl virus (TYLCV) is a devastating disease of tomato (Solanum lycopersicum) that can be effectively controlled by the deployment of resistant cultivars. The TYLCV-resistant line TY172 carries a major recessive locus for TYLCV resistance, designated ty-5, on chromosome 4. In this study, the association between 27 polymorphic DNA markers, spanning the ty-5 locus, and the resistance characteristics of individual plants inoculated with TYLCV in 51 segregating recombinant populations were analyzed. These analyses localized ty-5 into a 425 bp region containing two transversions: one in the first exon of a gene encoding the tomato homolog of the messenger RNA surveillance factor Pelota (Pelo), and a second in its proximal promoter. Analyses of susceptible and resistant lines revealed that the relative transcript level of the gene remained unchanged, regardless of whether the plants were infected with TYLCV or not. This suggests that the polymorphism discovered in the coding region of the gene controls the resistance. Silencing of Pelo in a susceptible line rendered the transgenic plants highly resistant, while in the resistant line TY172 had no effect on symptom development. In addition, over-expression of the susceptible allele of the gene in the resistant TY172 line rendered it susceptible, while over-expression of the resistant allele in susceptible plants had no effect. These results confirm that Pelo is the gene controlling resistance at the ty-5 locus. Pelo, implicated in the ribosome recycling-phase of protein synthesis, offers an alternative route to promote resistance to TYLCV and other viruses. Tomato is one of the most important food crops worldwide, providing phytonutrients and color to our diet. Tomato yellow leaf curl virus (TYLCV) is one of the most devastating viruses of cultivated tomatoes and a key limiting factor to tomato production in major tomato-growing areas. The management of TYLCV is difficult because its whitefly vector populations can reach high numbers and relies heavily on the application of hazardous chemicals (insecticides). Breeding TYLCV-resistant tomato cultivars provides an attractive, environmentally friendly strategy to reduce yield losses caused by the virus. Considerable efforts have been invested in breeding TYLCV-resistant tomato cultivars. The discovery and utilization of genes controlling resistance can expedite the breeding process and highlight innate means to promote such resistance. Here we report the discovery of the gene controlling TYLCV resistance at the ty-5 locus. It was found that the messenger RNA surveillance factor Pelo is responsible for this resistance. Our discovery, together with the recent discovery of the gene controlling resistance at the Ty-1/Ty-3 locus, can lead to precision pyramiding of these two genes to enhance the spectrum of resistance of tomato plants to TYLCV, and possibly to other begomoviruses.