Biodiversity of Tricholoma matsutake (syn. T. nauseousm) and its related species based on repetitive DNA and genomics.

Tricholoma matsutake and its related species are ectomycorrhizal Agaricomycetes that produce prized mushrooms collectively called “matsutake.” These mushrooms are mainly distributed in the Northern Hemisphere. In this review, we describe both the pioneering work and recent advances in our understanding of the distribution and evolution of matsutake, with a special focus on genomic studies. DNA sequence analyses revealed that T. caligatum was the earliest species within this group, followed by T. fulvocastaneum, the cluster with T. ilkkae, T. dulciolens, and T. bakamatsutake, and finally the cluster with T. murrillianum, T. mesoamericanum, T. anatolicum, and T. matsutake. Although analyses based on mobile DNAs and whole-genome sequences revealed a similar clustering pattern, there are distinct differences in the distribution of mobile DNAs and genomic structure of T. bakamatsutake and T. matsutake. Furthermore, repetitive DNA can be used as markers to distinguish among strains and populations of T. matsutake from different geographical regions, including identifying dispersals of basidiospores. “Telomere-to-telomere genome sequencing” analyses unearthed that both T. matsutake and T. bakamatsutake underwent explosive multiplications of retrotransposons within their genomes but with different mobile DNA elements expanded between them. Contrastingly, the structure of the mating loci between T. matsutake and T. bakamatsutake is highly conserved.