Within the framework of the CSP project 'Metatranscriptomics of Forest Soil Ecosystems', we are aiming to explore the interaction of forest trees with communities of soil fungi, including ectomycorrhizal symbionts that dramatically affect bioenergy-relevant plant growth, and saprotrophic soil fungi impacting carbon sequestration in forests. We are sequencing the metatranscriptome of soil fungi in ecosystems representative of major Earth ecosystems, the boreal, temperate and mediterranean forests. We are also sequencing the genome of the most abundant fungal species harvested on studied sites to serve as the foundation for a reference database for metagenomics of fungi and for a comprehensive survey of the potential soil fungal metabolome.