Functional characterization of conserved putative effector proteins in the Sebacinales

印度梨形孢菌（Piriformospora indica）和与之密切相关的担子菌Sebacina vermifera（MAFF 305830）属于生态学上广泛分布的Sebacinales，该目在进化早期从伞菌亚门（Agaricomycotina）分支出来，具有广泛的菌根类型。P. indica和S.蠕虫是两种根内生菌，其显示出宽宿主谱的有益效果，例如促进生长和增加对病原体的抗性。P. indica分离自印度塔尔沙漠的木本灌木Prosopis juliflora和Zizyphus nummularia的根际，但环境分子分析揭示了全世界各种植物（包括兰花和拟南芥）中广泛分布的密切相关序列。S. Vermifera分离自陆地澳大利亚兰花（Cyrtostylis reniformis），并且由于其在这些宿主中刺激种子萌发和幼苗发育的能力而被认为是兰花菌根真菌（ORM）。与JGI合作，对S.以200倍覆盖率对蠕虫进行测序。已经建立了这种真菌的遗传转化，并使用比较基因组学和转录组学的生物信息学工具（微阵列和RNA-seq）来鉴定植物中的响应基因。比较结果表明，一个核心的推定效应蛋白是保守的相关sebacinoid分离物，但似乎是不存在的更远的相关共生体和腐食性真菌。关于如何sebacinoid真菌建立自己在代谢活跃的根细胞不同的主机和植物如何重新编程，以提高性能的见解，我们建议使用综合方法，依赖于反向遗传学，转录组学，细胞生物学，生物化学和比较基因组学的组合，以找到以下问题的答案：A） 印楝和印度楝之间是否存在功能保守的效应子？蠕虫？（B） 类癸二酸酯效应蛋白如何介导宿主适应和互惠共生？C）、 生态学上不同的根内生菌有共同的定植机制和信号传导吗？

Piriformospora indica and the closely related basidiomycete Sebacina vermifera (MAFF 305830) belong to the ecologically widely distributed Sebacinales, an order that branched off the Agaricomycotina early in the evolution and harbors a broad spectrum of mycorrhizal types. P. indica and S. vermifera are both root endophytes that display wide-host spectrum beneficial effects, such as growth promotion and increased resistance to pathogens. P. indica was isolated from the rhizosphere of the woody shrubs Prosopis juliflora and Zizyphus nummularia at the Indian Thar desert but environmental molecular analyses have unravelled a ubiquitous distribution of closely related sequences within various plants worldwide including orchids and Arabidopsis. S. vermifera was isolated from a terrestrial Australian orchid (Cyrtostylis reniformis) and is considered an orchid mycorrhizal fungus (ORM) because of its capability to stimulate seed germination and seedling development in these hosts. In cooperation with the JGI the 35 Mb genome of S. vermifera was sequenced with 200 fold coverage. The genetic transformation of this mycobiont has been established and bioinformatics tools for comparative genomics and transcriptomics (microarrays and RNA-seq) were used to identify the in planta-responsive genes. The comparison has revealed that a core of putative effector-proteins is conserved in the related sebacinoid isolates but seems to be absent in more distantly related symbionts and saprotrophic fungi. With respect to insights into how sebacinoid fungi establishes themselves in metabolically active root cells of different hosts and how the plants are reprogrammed for enhanced performance, we propose to use integrated approaches that rely on the combination of reverse genetics, transcriptomics, cell biology, biochemistry, and comparative genomics to find answers to the following questions:A) Are there functionally conserved effectors between P. indica and S. vermifera?B) How do the sebacinoid effector proteins mediate host accommodation and mutualism? C) Do ecologically different root endophytes share common colonization mechanisms and signalling?