Effector genes of Xanthomonas axonopodis pv. vesicatoria promote transmission and enhance other fitness traits in the field.
Effector genes of Xanthomonas axonopodis pv. vesicatoria promote transmission and enhance other fitness traits in the field.
复制标题
DOI：
10.1534/genetics.166.2.693
复制
发表时间：
2004-02
期刊：
影响因子：
3.3
通讯作者：
Gale Wichmann;J. Bergelson
中科院分区：
文献类型：
--
作者：
Gale Wichmann;J. Bergelson
在农作物中建立持久的抗病性，其中大部分植物防御是通过效应子-R基因相互作用提供的，由于病原体通过失去相应的效应子基因来克服R基因抗性的能力而变得复杂。许多提出的在田间维持抗病性的方法依赖于效应基因损失导致病原体的适应性成本的想法。在这篇文章中，我们测试效应基因功能丧失的适应性成本。我们创造了定向敲除多达四个效应基因的细菌植物病原体Xanthomonaxonopodispv。vesicatoria（Xav）的，并检查了功能基因产物的损失对几个重要的健身参数在该领域的影响。这些性状包括传播、病变发展和附生生存。我们发现，所有四个效应基因的产品有显着的，往往是加性的健身性状的影响。额外的温室试验揭示了效应基因损失对植物生长的影响，并进一步表明对病变发展的影响与对生长的影响是分开的。可观察到的健身效果的三个质粒携带的效应基因依赖于功能avrBs 2的损失，表明复杂的功能相互作用与Xav的效应基因之间存在。
Establishing durable disease resistance in agricultural crops, where much of the plant defense is provided through effector-R gene interactions, is complicated by the ability of pathogens to overcome R gene resistance by losing the corresponding effector gene. Many proposed methods to maintain disease resistance in the field depend on the idea that effector gene loss results in a fitness cost to the pathogen. In this article we test for fitness costs of effector gene function loss. We created directed knockouts of up to four effector genes from the bacterial plant pathogen Xanthomonas axonopodis pv. vesicatoria (Xav) and examined the effect of the loss of a functional gene product on several important fitness parameters in the field. These traits included transmission, lesion development, and epiphytic survival. We found that the products of all four effector genes had significant and often additive effects on fitness traits. Additional greenhouse tests revealed costs of effector gene loss on in planta growth and further showed that the effects on lesion development were separable from the effects on growth. Observable fitness effects of the three plasmid-borne effector genes were dependent upon the loss of functional avrBs2, indicating that complex functional interactions exist among effector genes with Xav.