Title: | Unisexual reproduction promotes competition for mating partners in the global human fungal pathogen Cryptococcus deneoformans |
Author(s): | Fu C; Thielhelm TP; Heitman J; |
Address: | "Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, United States of America" |
DOI: | 10.1371/journal.pgen.1008394 |
ISSN/ISBN: | 1553-7404 (Electronic) 1553-7390 (Print) 1553-7390 (Linking) |
Abstract: | "Courtship is pivotal for successful mating. However, courtship is challenging for the Cryptococcus neoformans species complex, comprised of opportunistic fungal pathogens, as the majority of isolates are alpha mating type. In the absence of mating partners of the opposite mating type, C. deneoformans can undergo unisexual reproduction, during which a yeast-to-hyphal morphological transition occurs. Hyphal growth during unisexual reproduction is a quantitative trait, which reflects a strain's ability to undergo unisexual reproduction. In this study, we determined whether unisexual reproduction confers an ecological benefit by promoting foraging for mating partners. Through competitive mating assays using strains with different abilities to produce hyphae, we showed that unisexual reproduction potential did not enhance competition for mating partners of the same mating type, but when cells of the opposite mating type were present, cells with enhanced hyphal growth were more competitive for mating partners of either the same or opposite mating type. Enhanced mating competition was also observed in a strain with increased hyphal production that lacks the mating repressor gene GPA3, which contributes to the pheromone response. Hyphal growth in unisexual strains also enables contact between adjacent colonies and enhances mating efficiency during mating confrontation assays. The pheromone response pathway activation positively correlated with unisexual reproduction hyphal growth during bisexual mating and exogenous pheromone promoted bisexual cell fusion. Despite the benefit in competing for mating partners, unisexual reproduction conferred a fitness cost. Taken together, these findings suggest C. deneoformans employs hyphal growth to facilitate contact between colonies at long distances and utilizes pheromone sensing to enhance mating competition" |
Keywords: | "Cell Communication Cell Fusion Cryptococcus/genetics/pathogenicity Cryptococcus neoformans/*genetics/pathogenicity Fungal Proteins/genetics Genes, Mating Type, Fungal/*genetics/physiology Hyphae/genetics Pheromones Reproduction/genetics Reproduction, Asex;" |
Notes: | "MedlineFu, Ci Thielhelm, Torin P Heitman, Joseph eng R01 AI039115/AI/NIAID NIH HHS/ R01 AI050113/AI/NIAID NIH HHS/ R37 AI039115/AI/NIAID NIH HHS/ Research Support, N.I.H., Extramural 2019/09/20 PLoS Genet. 2019 Sep 19; 15(9):e1008394. doi: 10.1371/journal.pgen.1008394. eCollection 2019 Sep" |