Symbiosis-dependent microbiome patterning in Lotus japonicus roots

点击翻译按钮获取中文摘要

Sequencing a number of microbiomes from the legume Lotus japonicus provided great insights into the complexity of endophytes present in the rhizosphere and associated with the host root. However, our knowledge on spatio-temporal colonization patterns and any cross-talk in between these intercellularly colonizing bacteria and fungi is sparse as these information cannot be retrieved from global sequencing data. Furthermore, almost all genetic studies in legumes that assessed host genes for their function in controlling colonization by symbiotic microbes such as rhizobia and arbuscular mycorrhiza fungi (AMF) have been conducted by applying mono-association setups. However, the situation is fundamentally different in natural soils, where legume roots are colonized by multiple microbes simultaneously. Therefore, this proposal aims to increase complexity in the experimental setup by addressing the following aspects:1. Assessing a range of symbiosis mutants for their performance in natural soils. Based on our pilot experiments we will screen a collection of Lotus mutants for their ability to bypass regulatory networks that are currently considered to be indispensable for RNS. Strains colonizing these mutants will be identified. 2. Large-scale testing of mono-associations initially using 70 isolates from a bacterial core collection that was generated from Lotus japonicus roots. The most effective colonizers will be combined to a minimal synthetic community (minimal SynCom).3. Generation of marker strains within the minimal SynCom.4. Analysing distribution patterns of these marker strains within the host root and initial analysis of possible host factors controlling them.