Analysis of mfbA alleles of the eubasidiomycete Lentinus edodes

A novel gene, Le-Dd10, is involved in fruiting body formation of Lentinula edodes

The cDNA library prepared from Lentinula edodes, Hokken 600 (H600), primordia was screened using cDNA expressed specifically in Dictyostelium discoideum prestalk as a probe. Twenty-one clones, Le-Dd1 ~ 21, were isolated from the L. edodes primordia cDNA library. Functional analysis of each gene was carried out by transformation into protoplast cells from L. edodes Mori 252 (M252) mycelia with the overexpression vector pLG-RasF1 of each gene because M252 protoplast cells were transformed with an 11-fold higher efficiency than H600 cells. Transformants with the overexpression vector of Le-Dd10 formed a fruiting body at almost the same time as H600, a positive control, although M252, a negative control, did not form a fruiting body under culture conditions. This suggested that Le-Dd10 is involved in the formation of fruiting bodies. Single-strand conformation polymorphism analysis revealed that Le-Dd10 is located on No. 4 linkage group of L. edodes. The properties of Le-Dd10 products were investigated by Western blotting analysis using polyclonal antibodies against GST:Le-Dd10 fusion proteins. As a result, 56-kDa, 27-kDa, and 14-kDa protein bands appeared in primordial and fruiting body stages, although the expected molecular weight of the Le-Dd10 product was 50 kDa.

Decreased zinc ion accumulation by the basidiomycete Lentinus edodes over-expressing L. edodes PriA gene

The information that the deduced expression product of Lentinus edodes priA gene consists of N-terminal hydrophobic sequence, putative zinc-binding motifs and C-terminal membrane-binding-promoting unique sequence led us to analyze its function in L. edodes. Here L. edodes monokaryotic cells over-expressing priA gene were found to exhibit a remarkably decreased accumulation of zinc ion, indicating the involvement of the priA gene in regulation of the intracellular zinc concentration.