Mutualistic interactions on a knife-edge between saprotrophy and pathogenesis
Claire Veneault-Fourrey and Francis Martin
27 April 2011, Curr Opin Plant Biol. 14(4):444-50; doi: 10.1016/j.pbi.2011.03.022.
Saprophytic, ectomycorrhizal (ECM) and pathogenic fungi play a key role in carbon and nutrient cycling in forest ecosystems. Whereas more than 50 genomes of saprotrophic and pathogenic fungi have been published, only two genomes of ECM fungi, Laccaria bicolor and Tuber melanosporum, have been released. Comparative analysis of the genomes of biotrophic species highlighted convergent evolution. Mutualistic and pathogenic biotrophic fungi share expansion of genome size through transposon proliferation and common strategies to avoid plant detection. Differences mainly rely on nutritional strategies. Such analyses also pinpointed how blurred the molecular boundaries are between saprotrophism, symbiosis and pathogenesis. Sequencing of additional ECM species, as well as soil saprotrophic fungi, will facilitate the identification of conserved traits for ECM symbiosis and those leading to the transition from white-rotting and brown-rotting to the ECM lifestyle.
Harnessing omics for understanding the ecology of ECM fungi. Understanding how saprotrophic, symbiotic and pathogenic fungi achieve their lifestyle is crucial to understand their ecological functions, and their subsequent impact on the fate of plant communities. Several hundred species are active in soils and on-going genomics, metagenomics and metatranscriptomics studies will uncover the functions encoded in their genomes as well as their expressed transcripts. These sequenced genomes will provide baseline genomic information that enables scientists to investigate the interactions between fungal and plant communities.
Veneault-Fourrey C, Martin F. Mutualistic interactions on a knife-edge between saprotrophy and pathogenesis. Curr Opin Plant Biol. 2011 Aug;14(4):444-50. doi: 10.1016/j.pbi.2011.03.022. Epub 2011 Apr 27. Review. PubMed PMID: 21530366.