The Preliminary Study On The Structure Of A Mating Type Loci In Pleurotus Eryngii Var. Nebrodensis And Pleurotus Eryngii Var. Ferulae

In most heterothallic mushroom species, mating is dependant on an incompatibility system determined by two loci each with multiple alleles (the A and B mating type loci). In this study, we investigated the genetic structure of the A mating type loci in Pleurotus sp. Pleurotus eryngii var. nebrodensis (BaiLingGu) and Pleurotus eryngii var. ferulae (AWeiGu) using both degenerate PCR and long PCR methods because the hypervariety of the mating type loci.The test strains were 8 homokaryotic isolates from 4 cultivated P. eryngii var. nebrodensis strains and 2 isolates from wild P. eryngii var. ferulae strains. Three pairs of isolates from P. eryngii var. nebrodensis had the identical mating type in A loci determined by the classical genetics methods. After successfully having cloned the A loci from 6 P. eryngii var. nebrodensis isolates and 2 P. ferulae isolates, the A loci sequence revealed that the identical mating type factors determined by the classical genetics methods had the same nucleotides sequence in A loci. So, it proved that the the classical genetics methods and the molecular methods were consistent in judging the mating type. Addtionally, the sequence of 488A4 and 485A4 were the same with 465a2 in the A loci, suggesting the two species genetic relationships were so close.The A mating type loci were consisted of a pair of divergently hoeodomain transcription genes which encoding homeodomain protein HD1 and HD2, respectively. The HD1 from the 8 isolates (6 isolates from P. eryngii var. nebrodensis and 2 isolates from P. eryngii var. ferulae) contained both the nuclear localization signals (NLS) and coiled-coil domains (CCDS). However, exception of 485A3 and 488A3, which didn't contain the NLS, the HD2 in the rest isolates had both NLS and CCDs.