Comparative Analysis of Viromes Identified in Multiple Macrofungi

Area of Science:

• Mycology and Virology
• Soil Ecology and Fungal Biology
• Genomics and Bioinformatics

Background:

• Macrofungi are crucial for soil elemental cycling in terrestrial ecosystems.
• Fungal viruses are prevalent in filamentous fungi and can impact host physiology.
• The composition and evolutionary dynamics of macrofungal viruses remain largely unexplored.

Purpose of the Study:

• To characterize the virome of four macrofungi species: *Trametes versicolor*, *Coprinellus micaceus*, *Amanita strobiliformis*, and *Trametes hirsuta*.
• To investigate the phylogenetic relationships and abundance of identified mycoviruses.
• To compare mycovirus diversity and abundance between macrofungi and phytopathogenic fungi.

Main Methods:

• Collection of ninety macrofungi strains from China.
• Generation of four mixed RNA pools based on fungal species.
• RNA sequencing, sequence assembly, annotation, and phylogenetic analysis.
• Metatranscriptomic analysis to detect and quantify mycoviruses.

Main Results:

• Characterization of twenty novel viruses or viral fragments across the four macrofungi species.
• Phylogenetic classification of viral contigs into ten viral families/orders, including widely distributed ambi-like viruses.
• Significantly lower mycovirus abundance and diversity in the studied macrofungi (*Basidiomycota*) compared to broad-host phytopathogenic fungi (*Ascomycota*).

Conclusions:

• This study provides the first demonstration of multiple mycoviruses in *Amanita strobiliformis*, *Coprinellus micaceus*, *Trametes hirsute*, and *Trametes versicolor* using metatranscriptomics.
• The findings expand the understanding of mycoviral diversity and composition within macrofungi.
• The research contributes valuable data to the field of fungal virology, highlighting differences in viral loads between fungal groups.