Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists

  title={Convergent losses of decay mechanisms and rapid turnover of symbiosis genes in mycorrhizal mutualists},
  author={Annegret Kohler and Alan Kuo and L{\'a}szl{\'o} G. Nagy and Emmanuelle Morin and Kerrie W. Barry and François Buscot and Bj{\"o}rn Canb{\"a}ck and Cindy Choi and Nicolas Cichocki and Alicia Clum and Jan Colpaert and Alex Copeland and Maur{\'i}cio Dutra Costa and Jeanne Dor{\'e} and Dimitrios Floudas and Gilles Gay and Mariangela Girlanda and Bernard Henrissat and Sylvie Herrmann and Jaqueline Hess and N H{\"o}gberg and Tomas Johansson and Hassine Radhouane Khouja and Kurt LaButti and Urs Lahrmann and Anthony Levasseur and Erika A. Lindquist and Anna Lipzen and Roland Marmeisse and Elena Martino and Claude Murat and Chew Yee Ngan and Uwe Nehls and Jonathan M. Plett and Anne Pringle and Robin A. Ohm and Silvia Perotto and Martina Peter and Robert Riley and Francois Rineau and Joske Ruytinx and Asaf A. Salamov and Firoz Shah and Hui Sun and Mika Tapio Tarkka and Andrew J. Tritt and Claire Veneault-Fourrey and Alga Zuccaro and Anders Tunlid and Igor V. Grigoriev and David S. Hibbett and Francis M. Martin},
  journal={Nature Genetics},
To elucidate the genetic bases of mycorrhizal lifestyle evolution, we sequenced new fungal genomes, including 13 ectomycorrhizal (ECM), orchid (ORM) and ericoid (ERM) species, and five saprotrophs, which we analyzed along with other fungal genomes. Ectomycorrhizal fungi have a reduced complement of genes encoding plant cell wall–degrading enzymes (PCWDEs), as compared to their ancestral wood decayers. Nevertheless, they have retained a unique array of PCWDEs, thus suggesting that they possess… 

Rapid Divergence of Genome Architectures Following the Origin of an Ectomycorrhizal Symbiosis in the Genus Amanita

The aim was to identify the defining features of EM genomes, but analyses suggest no clear differentiation of genome size, gene repertoire size, or transposable element content between EM and AS species.

Large-scale genome sequencing of mycorrhizal fungi provides insights into the early evolution of symbiotic traits

This study samples ecologically dominant fungal guilds for which there were previously no symbiotic genomes available, including ectomycorrhizal Russulales, Thelephorales and Cantharellales, and shows that transitions from saprotrophy to symbiosis involve widespread losses of degrading enzymes acting on lignin and cellulose.

Evolutionary innovations through gain and loss of genes in the ectomycorrhizal Boletales

Novel insights are provided on the understanding of the mechanisms that influence the evolutionary diversification of boletes and symbiosis evolution and the rate of gene duplication is constant along the backbone of Boletales phylogeny with large loss events in lineages leading to several families.

Genetic determinants of endophytism in the Arabidopsis root mycobiome

It is reported that root mycobiota members evolved from ancestors with diverse lifestyles and retained large repertoires of plant cell wall-degrading enzymes (PCWDEs) and effector-like small secreted proteins, and identified and validated the pectin degrading enzyme family PL1_7 as a key component linking aggressiveness of endophytic colonization to plant health.

Comparative genomics provides insights into the lifestyle and reveals functional heterogeneity of dark septate endophytic fungi

The genomes of two common DSE of semiarid areas were sequenced and analyzed and low levels of convergence in their gene family evolution were observed, suggesting that, despite originating from the same habitat, these two fungi evolved along different evolutionary trajectories and display considerable functional differences within the endophytic lifestyle.

Genome and evolution of the arbuscular mycorrhizal fungus Diversispora epigaea (formerly Glomus versiforme) and its bacterial endosymbionts.

The D. epigaea genome showed a pattern of substantial gene duplication and differential evolution of gene families, including glycosyltransferase family 25, whose activities are exclusively lipopolysaccharide biosynthesis.

Comparative genomics and transcriptomics depict ericoid mycorrhizal fungi as versatile saprotrophs and plant mutualists.

The ERM fungal gene repertoire reveals a capacity for a dual saprotrophic and biotrophic lifestyle, which may reflect an incomplete transition from saprotrophy to the mycorrhizal habit, or a versatile life strategy similar to fungal endophytes.

A Survey of the Gene Repertoire of Gigaspora rosea Unravels Conserved Features among Glomeromycota for Obligate Biotrophy

The characterization of the gene repertoire from an AM fungal species belonging to the order of Diversisporales and its comparison with the gene sets of R. irregularis and Gigaspora margarita reveal that AM fungi share several features linked to mutualistic obligate biotrophy.

Genes conserved for arbuscular mycorrhizal symbiosis identified through phylogenomics

It is demonstrated that phylogenomics is an effective strategy to identify a set of evolutionarily conserved genes required for AMS and that mutants in six previously uncharacterized AMS-conserved genes are all impaired in AMS.

The genome of Rhizophagus clarus HR1 reveals a common genetic basis for auxotrophy among arbuscular mycorrhizal fungi

Several new genes that are absent from the genomes of AM fungi are found in addition to the genes previously identified as missing, implying that AM fungi may have a higher dependency on host plants than other biotrophic fungi.



The genome of Laccaria bicolor provides insights into mycorrhizal symbiosis

The predicted gene inventory of the L. bicolor genome points to previously unknown mechanisms of symbiosis operating in biotrophic mycorrhizal fungi, providing an unparalleled opportunity to develop a deeper understanding of the processes by which symbionts interact with plants within their ecosystem to perform vital functions in the carbon and nitrogen cycles that are fundamental to sustainable plant productivity.

Genome of an arbuscular mycorrhizal fungus provides insight into the oldest plant symbiosis

The genome of Rhizophagus irregularis provides insight into genes involved in obligate biotrophy and mycorrhizal symbioses and the evolution of an ancient asexual organism, and is of fundamental importance to the field of genome evolution.

The Plant Cell Wall–Decomposing Machinery Underlies the Functional Diversity of Forest Fungi

Fungal nutritional mode diversification suggests that the boreal forest biome originated via genetic coevolution of above- and below-ground biota through convergent evolution and divergence among fungal decomposers.

Ectomycorrhizal lifestyle in fungi: global diversity, distribution, and evolution of phylogenetic lineages

In conclusion, EcM fungi are phylogenetically highly diverse, and molecular surveys particularly in tropical and south temperate habitats are likely to supplement to the present figures.

Effector MiSSP7 of the mutualistic fungus Laccaria bicolor stabilizes the Populus JAZ6 protein and represses jasmonic acid (JA) responsive genes

It is demonstrated that the MiSSP7 (Mycorrhiza-induced small secreted protein-7) protein of the beneficial fungus Laccaria bicolor interacts with host plant JA signaling repressors and, in contrast to biotrophic pathogens, promotes symbiosis by blocking JA action.

Asynchronous origins of ectomycorrhizal clades of Agaricales

  • M. RybergP. B. Matheny
  • Environmental Science, Biology
    Proceedings of the Royal Society B: Biological Sciences
  • 2011
While it is demonstrated support for asynchronous origins of ECM Agaricales, the timing of such events appears to have occurred more recently than suggested by the first hypothesis, first during the Cretaceous and later during the Palaeogene.

Mycorrhizal fungi as drivers of ecosystem processes in heathland and boreal forest biomes

What unites mycorrhizas in heathland and boreal forest biomes is their apparent affinity for acidic organic soils of inherently low accessibility of the major nutrients nitrogen (N) and phosphorus (P).

Carbon availability triggers the decomposition of plant litter and assimilation of nitrogen by an ectomycorrhizal fungus

The data suggest that the expression of the decomposition and nitrogen assimilation processes of EMF can be tightly regulated by the host carbon supply and that the availability of inorganic nitrogen as such has limited effects on saprotrophic activities.