The genetic structure and diversity of the A and B mating-type genes from the tropical oyster mushroom, Pleurotus djamor.
In most heterothallic mushroom species, inbreeding is avoided by 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 mating-type loci in the tropical oyster mushroom Pleurotus djamor using both positional cloning and degenerate PCR methods. DNA sequences from genomic regions cosegregating with the mating-type loci of P. djamor revealed homeodomain transcription factors (A) and pheromone receptors (B), suggesting the genetic basis for mating-type determination in P. djamor is the same as in the model mushroom species. Three pheromone receptors were detected in a single homokaryotic isolate of P. djamor. Only one pair of homeodomain genes was detected in the A mating-type region. It is hypothesized that the A mating-type locus of P. djamor is comprised of only one homeodomain pair, which may explain the lower number of A mating-type alleles relative to other mushroom species.
James
Timothy Y
TY
Department of Biology, Box 90338, Duke University, Durham, NC 27708, USA. tyj2@duke.edu
Liou
Shian-Ren
SR
Vilgalys
Rytas
R
D000595:Amino Acid Sequence; D002874:Chromosome Mapping; D015723:Gene Library; D005800:Genes, Fungal; D049770:Genes, Mating Type, Fungal; D014644:Genetic Variation; D008969:Molecular Sequence Data; D010802:Phylogeny; D020076:Pleurotus / Q000145:classification / Q000235:genetics*; D043563:Receptors, Pheromone / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology
D043563:Receptors, Pheromone; D014157:Transcription Factors