Cymbiomics: multipartite interactions and a large-scale approach to pinpointing symbiotic competence of cyanobacteria

Cymbiomics：多方相互作用和大规模方法来确定蓝藻的共生能力

• 批准号: 515101361
• 负责人: Professor Dr. Jan de Vries
• 金额: --
• 依托单位: Abteilung Experimentelle Phykologie und Sammlung von Algenkulturen (EPSAG)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/515101361?language=en
• 关键词: Cymbiomics; multipartite; interactions; large; scale

The symbiotic interaction between cyanobacteria and eukaryotic hosts had a profound impact on the evolution of life on this planet. It was a cyanobacterial symbiont that eventually was turned into the chloroplasts for carbon-fixation. Yet, there is another prominent type of cyanobacteria in symbiosis (cyanobionts). Here, the interaction revolves around the ability of cyanobionts to perform nitrogen-fixation. In several cases, these cyanobionts are tightly integrated into the host body but have not (yet) been domesticated into an organelle. Such extant interactions are best-described in land plants (Embryophyta), but also the fungus Geosiphon—for which one of the few known natural populations thrives close to Göttingen. The manifold occurrence of symbiotic cyanobacteria, many of which are still capable of living together and apart from their host, warrants the question what made them eligible for a symbiosis in the first place. In all cyanobacterial symbioses, multipartite interactions between the host, the cyanobiont, and an associated microbial community occur. We therefore hypothesize that the cyanobacteria capable to be cyanobionts must have the ability to not only communicate with their hosts but also to function in—and perhaps even shape—a multi-organism biofilm. Here we will explore two questions: i) What manifests the symbiotic competence of these cyanobacterial lineages? and ii) Is the competence of the cyanobacterial partner determined by the capacity to recruit the functionally correct microbiome? We will carry out a three-pronged approach. First, we will leverage the SAG collection in Göttingen and sequence cyanobacterial strains isolated from symbiotic and non-symbiotic conditions; contextualized with publicly available genomes, these data will be combined with genome-wide association studies and comparative genomics to pinpoint genetic factors that is common to all cyanobacteria that are clearly capable of symbiosis. Second, we will sample naturally occurring cyanobionts and their microbiome from multiple individuals of Geosiphon and the cyanobiont-bearing plants Gunnera, Azolla and Anthoceros. Third, we will use the Anthoceros lab system to phenotype the cyanobacterial strains sequenced for symbiotic competency and determine the microbiome of the Anthoceros–cyanobacteria symbiosis after cyanobacterial inoculation. Altogether, our data will determine factors linked to the symbiotic capabilities of the cyanobacteria—both in natural and cultivated cyanobionts. Possible follow-up studies will include generation of cyanobacteria that are knocked out in the identified candidate genes.

蓝藻和真核生物宿主之间的共生相互作用对地球上生命的进化产生了深远的影响。它是一种蓝藻共生体，最终被转化为叶绿体来固定碳。然而，在共生关系中还有另一种突出的蓝藻（蓝藻菌）。在这里，相互作用围绕蓝藻生物进行固氮的能力。在一些情况下，这些蓝藻生物与宿主体紧密结合，但尚未被驯化成细胞器。这种现存的相互作用在陆地植物（胚科植物）中得到了最好的描述，但在真菌地虹吸中也有，它是为数不多的已知自然种群之一，在Göttingen附近茁壮成长。共生蓝藻的多种出现，其中许多仍然能够生活在一起，并与宿主分开，这就证明了一个问题，即是什么使它们首先有资格成为共生关系。在所有蓝藻共生中，宿主、蓝藻和相关微生物群落之间存在多方相互作用。因此，我们假设能够成为蓝藻生物的蓝藻菌必须不仅具有与宿主交流的能力，而且还具有在多生物生物膜中发挥作用甚至可能形成多生物生物膜的能力。在这里，我们将探讨两个问题：i)是什么体现了这些蓝藻谱系的共生能力？以及ii)蓝藻伴侣的能力是否由招募功能正确的微生物组的能力决定？我们将坚持“三管齐下”。首先，我们将利用Göttingen的SAG收集并对从共生和非共生条件下分离的蓝藻菌株进行测序；与公开可用的基因组背景，这些数据将与全基因组关联研究和比较基因组学相结合，以查明所有蓝藻共同的遗传因素，显然能够共生。其次，我们将从Geosiphon和含有蓝藻的植物Gunnera， Azolla和Anthoceros的多个个体中取样自然产生的蓝藻菌及其微生物组。第三，我们将使用Anthoceros实验室系统对共生能力测序的蓝藻菌株进行表型分析，并确定蓝藻接种后Anthoceros - cyanobacteria共生的微生物组。总之，我们的数据将确定与蓝藻共生能力相关的因素-无论是在天然的还是培养的蓝藻。可能的后续研究将包括在确定的候选基因中被敲除的蓝藻的产生。