三类植物卵菌的全基因组比较

Genome-wide comparison of three types of plant pathogenic oomycete species

为有效防治由不同类型卵菌引起的植物病害,该研究对数据库中的霜霉、疫霉和腐霉3类不同卵菌的全基因组数据进行序列特征分析、同源性分析和共线性分析以及同源差异基因富集通路分析。结果显示,霜霉、疫霉和腐霉来自独立的谱系,且疫霉与霜霉的亲缘关系较近;疫霉的致病相关基因数量最多,主要有RxLR、CRN、NPP、NF和PcF基因家族,霜霉的致病相关基因数量次之,腐霉的致病相关基因数量最少;3类卵菌共确定了13392个同源基因,其中3类卵菌均共有的同源基因为3786个,不同菌种的同源基因数量差异较大,整体表现为疫霉>霜霉>腐霉;同源差异基因富集程度最高的前20个通路主要是基础代谢的通路和中间代谢通路,其中抗坏血酸和藻酸盐代谢、ABC转运蛋白和果糖和甘露糖代谢相对富集程度较高,基因数目也较多。

In order to control plant diseases caused by oomycetes,the genomic structure,homology and differential gene enrichment pathways of the whole genome sequences of three types of plant oomyce-tes species(Peronospora,Phytophthora and Pythium)were systematically studied.The results showed that Peronospora,Phytophthora and Pythium originated from independent lineages,and the genetic re-lationship between Peronospora and Phytophthora was closely related;the number of pathogenesisrelated genes in Phytophthora was the highest,these genes included RxLR,CRN,NPP,NF and PcF families.The number of pathogenesis-related genes in Peronospora was less than that in Phytophthora,and that in Pythium was the least.A total of 13392 homologous genes and 3786 homologous consen-sus genes were identified in the three types of plant oomycetes species.There were also significant dif-ferences in the number of homologous genes among different plant oomycetes species,and the overall tendency was Phytophthora>Peronospora>Pythium.The analysis of the enrichment pathways of ho-mologous differential genes showed that the top 20 pathways was mainly basal metabolic pathways and intermediate metabolic pathways,among them ascorbate and aldarate metabolism,ABC transporters and fructose and mannose metabolism were comparatively enriched and the genes were more abundant.