This genome was sequenced as a part of the large-scale multi-genome JGI CSP Saprotrophic Agaricomycotina Project (SAP), which focuses on the diversity and evolution of decay mechanisms, organismal phylogenetic relationships, and developmental evolution. A large collaborative effort led by the PI of this project, David Hibbett (Clark University) aims for master publication(s) of the SAP data analysis. Researchers who wish to publish analyses using data from unpublished SAP genomes are respectfully required to contact the PI and JGI to avoid potential conflicts on data use and coordinate other publications with the SAP master paper(s).
Lentinus tigrinus (Bull.)Fr. is a white rot fungus in the “core polyporoid clade” of the Polyporales. This order has been the target of multiple genome sequencing projects by the JGI, owing to its importance as a major group of wood decay fungi. Many species of Polyporales have characteristic substrate types, defined by host species as well as properties such as the size and age of the logs on which they occur. One reason to sample the genomes of multiple species of Polyporales is to understand the changes in gene contents and regulation that accompany shifts in substrate preferences. Lentinus tigrinus favors hardwoods, and it has the unusual property of frequently growing on dead wood that is emergent from water. In addition to its importance as a wood-decay species, L. tigrinus is also of interest from the perspective of morphological evolution. Lentinus tigrinus has gills (in mycological parlance, it is an “agaric”) but these are not homologous to the gills of most familiar mushrooms, such as button mushrooms (Agaricus bisporus) or oyster mushrooms (Pleurotus ostreatus), which are members of the Agaricales. Rather, L. tigrinus is derived from polypore ancestors, so it represents an independent origin of gills in the mushroom-forming fungi. In addition, there is a naturally occuring developmental mutant of L. tigrinus that produces a puffball-like “secotioid” form in which the gills are enclosed by a persistent veil of tissue (on the right in the photo). Agaricomycete fungi, like L. tigrinus, only produce fruiting bodies in the dikaryotic state, which is produced by the fusion of two mating-compatible haploid monokaryons (each derived from a single haploid basidiospore).