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The wood degrading fungus Schizophyllum commune is a model system for mushroom development. Here, we describe the 38.5 Mb assembled genome of this basidiomycete and application of whole genome expression analysis to study the 13,210 predicted genes. Comparative analyses of the S. commune genome revealed unique wood degrading machinery and mating type loci with the highest number of reported genes. Gene expression analyses revealed that one third of the 471 identified transcription factor genes were differentially expressed during sexual development. Two of these transcription factor genes were deleted. Inactivation of fst4 resulted in the inability to form mushrooms, whereas inactivation of fst3 resulted in more but smaller mushrooms than wild-type. These data illustrate that mechanisms underlying mushroom formation can be dissected using S. commune as a model. This will impact commercial production of mushrooms and the industrial use of these fruiting bodies to produce enzymes and pharmaceuticals

An experiment involving Aspergillus nidulans is conducted to examine the role of actin in apical growth and enzyme secretion of the said fungus. This involves the treatment of hyphae with cytochalasin A, a chemical that controls actin polymerization. Results show that normal apical growth, polarized enzyme secretion and hyphal tip shape are achieved by polymerizing actin cytoskeleton.

A research was conducted to investigate the localization of secretion and expression of a heterologous barley cysteine endopeptidase and the homologous main celobiohydrolase I in the filementous fungus Trichoderma reesei which expressed both proteins. A TRIzol reagent was utilized to isolate total RNA from the mycelia of T. reesei. Results showed that the recombinant cysteine proteinase was located in the hyphae at the colony edges. The hyphae accommodated several nuclei and a certain distance was always observed between the tip and the nucleus closest to it.

The genes defining multiple B mating types in the wood-rotting mushroom Schizophyllum commune are predicted to encode multiple pheromones and pheromone receptors. These genes are clustered in each of two recombinable and independently functioning loci, B[Alpha] and B[Beta]. A difference in specificity at either locus between a mated pair of individuals initiates an identical series of events in sexual morphogenesis. The B[Alpha]1 locus was recently found to contain genes predicted to encode three lipopeptide pheromones and a pheromone receptor with a seven-transmembrane domain. These gene products interact in hetero-specific pairs, the pheromone of one B[Alpha] specificity with the receptor of any one of the other eight B[Alpha] specificities, and are likely to activate a signaling cascade similar to that known for mating in Saccharomyces cerevisiae. We report here that the B[Beta]1 locus also contains at least three pheromone genes and one pheromone receptor gene, which function similarly to the genes in the B[Alpha]1 locus, but only within the series of B[Beta] specificities. A comparison of the DNA sequences of the B[Alpha]1 and B[Beta]1 loci suggests that each arose from a common ancestral sequence, allowing us to speculate about the evolution of this unique series of regulatory genes.

A study of the synthesis of endoglucanase and many hemicellulolytic enzymes in P- and S-group strains of Heterobasidion annosum through enzyme activity assays and isoelectric focusing reveals that xylamases, endoglucanases, mannases and alpha-galactosidases are synthesized by both strains of the fungus in liquid cultures with birch sawdust or pure xylan. Cultures with glucose alone as carbon source exhibit very low activities of the enzymes. The generation of hemicellulolytic and endoglucanase activities is related to an increase in the pH of the birch sandwich culture medium. The individual endoglucanases differ in their relative intensities between the two strains.