Centro Hispano-Luso de Investigaciones Agrarias (CIALE), Departamento de Microbiología y Genética, Universidad de Salamanca, Villamayor, Spain.
Plant Signal Behav. 2012 Dec;7(12):1667-75. doi: 10.4161/psb.22362. Epub 2012 Oct 16.
Millions of years of coevolution between plants and pathogens can leave footprints on their genomes and genes involved on this interaction are expected to show patterns of positive selection in which novel, beneficial alleles are rapidly fixed within the population. Using information about upregulated genes in maize during Colletotrichum graminicola infection and resources available in the Phytozome database, we looked for evidence of positive selection in the Poaceae lineage, acting on protein coding sequences related with plant defense. We found six genes with evidence of positive selection and another eight with sites showing episodic selection. Some of them have already been described as evolving under positive selection, but others are reported here for the first time including genes encoding isocitrate lyase, dehydrogenases, a multidrug transporter, a protein containing a putative leucine-rich repeat and other proteins with unknown functions. Mapping positively selected residues onto the predicted 3-D structure of proteins showed that most of them are located on the surface, where proteins are in contact with other molecules. We present here a set of Poaceae genes that are likely to be involved in plant defense mechanisms and have evidence of positive selection. These genes are excellent candidates for future functional validation.
数百万年来，植物和病原体之间的共同进化在它们的基因组上留下了痕迹，预计参与这种相互作用的基因会表现出正选择的模式，即在种群中快速固定新的有利等位基因。利用玉米在 Colletotrichum graminicola 感染过程中上调基因的信息和 Phytozome 数据库中可用的资源，我们在禾本科植物进化枝上寻找与植物防御相关的蛋白质编码序列上的正选择证据。我们发现了六个有正选择证据的基因，另外八个基因有间歇性选择的位点。其中一些已经被描述为在正选择下进化，但其他的则是首次报道，包括编码异柠檬酸裂解酶、脱氢酶、多药转运蛋白、含有假定亮氨酸丰富重复的蛋白质和其他具有未知功能的蛋白质的基因。将正选择的残基映射到蛋白质的预测 3-D 结构上表明，它们中的大多数位于表面，蛋白质与其他分子在那里接触。我们在这里提出了一组禾本科植物基因，这些基因可能参与植物防御机制，并具有正选择的证据。这些基因是未来功能验证的优秀候选基因。
