Identification and characterization of brt1, a gene down-regulated during B-regulated development in Schizophyllum commune

To identify genes regulated by the B mating-type genes a differential RNA d isplay was established for the homobasidiomycete Schizophyllum commune and a gene, brt1, was identified. The mRNA concerned is highly abundant in mono karyotic mycelia and is down-regulated in matings in which either the B gen es alone or else both the A and B genes are different between the mates. Th is places the gene brt1 under the control of the pheromone response system of S. commune encoded by the B mating type loci. Sequence analysis revealed similarity to a novel protein family, two members of which have been shown to inhibit translational re-initiation.