Arthroderma benhamiae (the teleomorph of Trichophyton mentagrophytes) mating type-specific genes.

This study first report to identify the mating type (-)-specific gene of alpha-box and the mating type (+)-specific gene of the high-mobility-group (HMG) DNA-binding domain in zoophilic dermatophytes of Arthroderma benhamiae in an effort to understand the epidemiological characteristics of Trichophyton mentagrophytes. The sequence of the alpha-box gene (1,387 bp) was found to contain two exons, from 184 to 475 bp and from 525 to 1,387 bp, coding a protein of 384 amino acids, beginning with a putative initiating methionine (ATG). The sequence of the HMG gene (1,910 bp) contained two exons, from 234 to 415 bp and from 479 to 1,457 bp, coding a protein of 386 amino acids, beginning with a putative initiating methionine (ATG). PCR analysis detected the alpha-box gene in A. benhamiae (-) mating type strains but not in (+) mating type strains. On the other hand, the HMG gene was detected in A. benhamiae (+) mating type strains but not in (-) mating type strains. These findings suggest that the HMG and alpha-box genes could be specific to the (+) and (-) mating types, respectively.