Evolution of mating pheromone and receptor genes in Pucciniomycotina

Authors: Henk, Daniel; Aime, Mary

Submitted to: Inoculum
Publication Type: Abstract Only
Publication Acceptance Date: 5/14/2007
Publication Date: 3/3/2008
Citation: Henk, D.A., Aime, M.C. 2008. Evolution of mating pheromone and receptor genes in Pucciniomycotina. Inoculum. 59(2):19

Interpretive Summary:

Technical Abstract: Mating pheromones and their receptors act as a switch controlling phenotypic changes required for successful mating in fungi. Although basidiomycete mating pheromones and their processing were first described in Rhodosporidium toruloides a “red yeast” in the Sporidiobolales, the receptor gene was never described, and much of the mating process remains unexplored in any species of Pucciniomycotina. We used published data from whole-genome-sequencing projects to detect putative mating pheromones and their receptor genes in several Pucciniomycotina. Primers were designed for direct amplification and sequencing of a putative receptor gene similar to Sterile 3 (ste3) and a closely linked gene similar to a putative nuclear localization protein from other red yeasts. Results suggest that pheromones and their receptors, as well as synteny around the pheromone receptor locus, are relatively conserved in the Sporidiobolales. Although only a single ste3 locus could be detected in Sporidiobolales genomes, three separate loci similar to ste3 were detected in the Puccinia graminis (Pucciniales) genome. In phylogenetic analyses the Puccinia STE3 sequences formed a well-supported clade at the base of the basidiomycetes while the Sporidiobolales sequences formed a well-supported clade nested within the basidiomycetes.