Specific distribution in homobasidiomycete hymenophores of the transcripts of Ras protein and G-protein α-subunit genes

Results of in situ RNA-RNA hybridization showed a complementary distribution of the transcripts of Ras protein gene (ras) and trimeric G-protein α-subunit gene (ga1) in the hymenophores of white-rot basidiomycete Lentinula edodes and ectomycorrhizal basidiomycete Lyophyllum shimeji. The ras gene is present mostly in outer region of trama (the region branching out into the subhymenium) and in trams cells, while the ga1 gene is present mostly in hymenium (on which a large number of basidiospores are formed) and in subhymenium (on the top of which hymenium is formed). This suggests that the ras and ga1 genes play distinct physiological roles in the hymenophores of both basidiomycete fungi.