Draft genome of Taphrina deformans
Taphrina deformans, commonly known as the peach leaf curl fungus, is an ascomycetous species belonging to the Taphrinomycotina, an heterogeneous basal lineage of the phylum Ascomycota (Fungi). As all other members of the genus Taphrina, T. deformans is dimorphic, i.e., it has a biotrophic hyphal state parasitic on plant tissue and a saprobic yeast state that grows on conventional culture media and may overwinter on plant surfaces. T. deformans is best known as the agent of ‘peach leaf curl’, a disease that affects orchards throughout the temperate regions of the world. Hosts include peach (Prunus persica) and to a lesser extent almond trees (P. dulcis). The significance of sequencing of the T. deformans genome is manifold. (i) T. deformans belongs to a basal lineage of ascomycetes whose other members are quite distinct in life style and life cycle, and includes the fission yeast Schizosaccharomyces pombe (genome sequencing completed) and the human pathogen Pneumocystis jirovecii (genome sequencing ongoing). Genome data will help ascertain the core gene set for ascomycetes and unveil the large amount of unrecognized phylogenetic diversity in this basal group. (ii) Comparison with genomes of other fungal plant pathogens (e.g. Magnaporthe grisea, Fusarium graminearum) may help identify putative pathogenicity genes in T. deformans and provide clues for investigating the mechanisms of plant-fungal interaction in the group of phytoparasites to which T. deformans belongs. The sequence data produced may also allow exploration at the molecular level of the basis for host specificity exhibited by this fungus, which appears to comprise two closely related forms on each of the possible hosts. (iii) Dimorphic switching is an important developmental process in many fungi and genome sequence data for T. deformans may prove useful in unravelling the molecular mechanisms involved, e.g., by comparison with other dimorphic fungi such as Ustilago maydis, Histoplasma capsulatum or Penicillium marnefeii, for which genome data is available.