The streamlined genome of Phytomonas spp. relative to human pathogenic kinetoplastids reveals a parasite tailored for plants.
The streamlined genome of Phytomonas spp. relative to human pathogenic kinetoplastids reveals a parasite tailored for plants.
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DOI：
10.1371/journal.pgen.1004007
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发表时间：
2014-02
期刊：
影响因子：
4.5
通讯作者：
Dollet M
中科院分区：
文献类型：
--
作者：
Porcel BM;Denoeud F;Opperdoes F;Noel B;Madoui MA;Hammarton TC;Field MC;Da Silva C;Couloux A;Poulain J;Katinka M;Jabbari K;Aury JM;Campbell DA;Cintron R;Dickens NJ;Docampo R;Sturm NR;Koumandou VL;Fabre S;Flegontov P;Lukeš J;Michaeli S;Mottram JC;Szöőr B;Zilberstein D;Bringaud F;Wincker P;Dollet M
锥虫科的成员感染许多生物体，包括动物、植物和人类。感染植物的锥虫被归为植物单胞菌属，未能反映这些原生生物广泛的生物学和病理学多样性。而一些植物单胞菌属（Phytomonas spp.）在植物的乳汁中或在果实或种子中繁殖，没有明显的致病性，其他一些寄生在韧皮部汁液中，折磨具有重要经济价值的植物，包括咖啡树、椰子和油棕榈。植物锥虫尚未在基因组水平上进行广泛研究，这是理解和控制发病机制的主要差距。我们描述了两种植物锥虫的基因组序列，一种致病性分离株从圭亚那椰子和一种无症状的分离株从大戟收集在法国。虽然这些寄生虫具有极其不同的致病性影响，但很少有基因是两者所独有的，绝大多数基因由两种分离株共享。值得注意的是，植物单胞菌属（Phytomonas spp.）基因组基本上由其大部分代谢酶的单拷贝基因组成，而其它锥虫例如利什曼原虫和锥虫具有多个旁系同源基因或家族。事实上，与其他锥虫基因组的比较揭示了一个高度精简的基因组，编码一个最小化的代谢系统，同时保存主要途径，并保留了完整的内膜细胞器，但没有证据表明功能的复杂性。植物单胞菌代谢基因的鉴定为建立这些难养寄生虫的体外培养提供了机会，并为控制农业植物病害提供了新的工具。一些植物锥虫，即生活在韧皮部汁液中的单细胞生物，是造成重要的棕榈病的原因，导致对其昆虫媒介频繁使用昂贵和有毒的杀虫剂。其他锥虫在乳胶管中繁殖而不损害其宿主。尽管这些锥虫的行为和影响范围很广，但它们被毫不客气地归为一个属：植物单胞菌属。一组分子探针已被用于其表征，但没有明确的同源性或分类已建立。我们已经测序的致病韧皮部特定的植物单胞菌的基因组从患病的南美椰子树和乳胶特定的分离物收集从一个明显健康的野生大戟在法国南部。在相互比较，并与人类致病性锥虫，植物单胞菌揭示了独特的紧凑的基因组，基本上由单拷贝基因组成，与绝大多数的基因共享的两个分离株，无论其对宿主的影响。糖代谢途径中的一组强酶与植物中发现的营养环境一致。这些遗传差异可能揭示了这两种独特的植物寄生虫行为差异的基础，并为我们今后寻找有效的作物病害寄生虫治疗方法指明了方向。
Members of the family Trypanosomatidae infect many organisms, including animals, plants and humans. Plant-infecting trypanosomes are grouped under the single genus Phytomonas, failing to reflect the wide biological and pathological diversity of these protists. While some Phytomonas spp. multiply in the latex of plants, or in fruit or seeds without apparent pathogenicity, others colonize the phloem sap and afflict plants of substantial economic value, including the coffee tree, coconut and oil palms. Plant trypanosomes have not been studied extensively at the genome level, a major gap in understanding and controlling pathogenesis. We describe the genome sequences of two plant trypanosomatids, one pathogenic isolate from a Guianan coconut and one non-symptomatic isolate from Euphorbia collected in France. Although these parasites have extremely distinct pathogenic impacts, very few genes are unique to either, with the vast majority of genes shared by both isolates. Significantly, both Phytomonas spp. genomes consist essentially of single copy genes for the bulk of their metabolic enzymes, whereas other trypanosomatids e.g. Leishmania and Trypanosoma possess multiple paralogous genes or families. Indeed, comparison with other trypanosomatid genomes revealed a highly streamlined genome, encoding for a minimized metabolic system while conserving the major pathways, and with retention of a full complement of endomembrane organelles, but with no evidence for functional complexity. Identification of the metabolic genes of Phytomonas provides opportunities for establishing in vitro culturing of these fastidious parasites and new tools for the control of agricultural plant disease. Some plant trypanosomes, single-celled organisms living in phloem sap, are responsible for important palm diseases, inducing frequent expensive and toxic insecticide treatments against their insect vectors. Other trypanosomes multiply in latex tubes without detriment to their host. Despite the wide range of behaviors and impacts, these trypanosomes have been rather unceremoniously lumped into a single genus: Phytomonas. A battery of molecular probes has been used for their characterization but no clear phylogeny or classification has been established. We have sequenced the genomes of a pathogenic phloem-specific Phytomonas from a diseased South American coconut palm and a latex-specific isolate collected from an apparently healthy wild euphorb in the south of France. Upon comparison with each other and with human pathogenic trypanosomes, both Phytomonas revealed distinctive compact genomes, consisting essentially of single-copy genes, with the vast majority of genes shared by both isolates irrespective of their effect on the host. A strong cohort of enzymes in the sugar metabolism pathways was consistent with the nutritional environments found in plants. The genetic nuances may reveal the basis for the behavioral differences between these two unique plant parasites, and indicate the direction of our future studies in search of effective treatment of the crop disease parasites.
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影响因子：
10.7
作者：
Bringaud, F;Biteau, N;Baltz, T
通讯作者：
Baltz, T
影响因子：
4.4
作者：
Aury JM;Cruaud C;Barbe V;Rogier O;Mangenot S;Samson G;Poulain J;Anthouard V;Scarpelli C;Artiguenave F;Wincker P
通讯作者：
Wincker P
影响因子：
1.5
作者：
Bringaud, F;García-Pérez, JL;Lopez, MC
通讯作者：
Lopez, MC
影响因子：
2.6
作者：
Andersson, Bjorn
通讯作者：
Andersson, Bjorn
影响因子：
1.5
作者：
Ackers, JP;Dhir, V;Field, MC
通讯作者：
Field, MC