PT  - JOURNAL ARTICLE
AU  - Hirokazu Toju
AU  - Akifumi S. Tanabe
AU  - Hirotoshi Sato
TI  - Network hubs in root-associated fungal metacommunities
AID  - 10.1101/270371
DP  - 2018 Jan 01
TA  - bioRxiv
PG  - 270371
4099  - http://biorxiv.org/content/early/2018/02/23/270371.1.short
4100  - http://biorxiv.org/content/early/2018/02/23/270371.1.full
AB  - Background: Although a number of recent studies have uncovered remarkable diversity of microbes associated with plants, understanding and managing dynamics of plant microbiomes remain major scientific challenges. In this respect, network analytical methods have provided a basis for exploring “hub” microbial species, which potentially organize community-scale processes of plant-microbe interactions.Methods: By compiling Illumina sequencing data of root-associated fungi in eight forest ecosystems across the Japanese Archipelago, we explored hubs within “metacommunity-scale” networks of plant-fungus associations. In total, the metadata included 8,080 fungal operational taxonomic units (OTUs) detected from 227 local populations of 150 plant species/taxa.Results: Few fungal OTUs were common across all the eight forests. However, in each metacommunity-scale network representing northern four localities or southern four localities, diverse mycorrhizal, endophytic, and pathogenic fungi were classified as “metacommunity hubs”, which were detected from diverse host plant taxa throughout a climatic region. Specifically, Mortierella (Mortierellales), Cladophialophora (Chaetothyriales), Ilyonectria (Hypocreales), Pezicula (Helotiales), and Cadophora (incertae sedis) had broad geographic and host ranges across the northern (cool-temperate) region, while Saitozyma/Cryptococcus (Tremellales/Trichosporonales) and Mortierella as well as some arbuscular mycorrhizal fungi were placed at the central positions of the metacommunity-scale network representing warm-temperate and subtropical forests in southern Japan.Conclusions: The network theoretical framework presented in this study will help us explore prospective fungi and bacteria, which have high potentials for agricultural application to diverse plant species within each climatic region. As some of those fungal taxa with broad geographic and host ranges have been known to increase the growth and pathogen resistance of host plants, further studies elucidating their functional roles are awaited.Abbreviations:DDBJDNA Data Bank of JapanITSinternal transcribed spacerOTUOperational taxonomic unitPERMANOVApermutational analysis of variancePERMDISPpermutational analysis for the multivariate homogeneity of dispersionsrRNAribosomal ribonucleic acid