2003 Volume 44 Issue 2 Article ID: jjom.H14-45
Photomorphogenesis of basidiomycetes was studied. Polyporus arcularius (Favolus arcularius) needs light for primordium and pileus-primordium formation. These photomorphogenetic events in this fungus involved similar photomorphogenetic processes: two essential light processes and an intervening dark process. The nature of these elementary processes in pileus-primordium formation was examined by the use of high temperature treatment (37°C-15min), which disrupted the photomorphogenetic process without any aftereffects. The action spectra for primordium and pileus-primordium formation were determined and the nature of blue light photoreceptor was discussed. The regulation of carbohydrate and nitrogen metabolism, especially on trehalose metabolism, in fruit-body formation of basidiomycetes, was also studied. Flammulina velutipes involves glycogen and trehalose as storage and translocates carbohydrate as is common to other mushrooms. The author and his co-workers found a novel key enzyme, α-glucose 1-phosphate (α-G1P), forming trehalose phosphorylase (TP), which regulated trehalose metabolism in basidiomycetes. TP was purified from Pleurotus ostreatus, and the holoenzyme was estimated to be a dimer of two identical subunits. TP regulated the synthesis of trehalose in mycelium and the phosphorolysis of trehalose to produce α-G1P and glucose in fruit-bodies. Complementary DNA for a gene encoding TP (PsTP) was cloned from Pleurotus sajor-caju. The PsTP gene is expressed in mycelium and fruit-bodies.
