| Title: | "Recapitulation of the sexual cycle of the primary fungal pathogen Cryptococcus neoformans var. gattii: implications for an outbreak on Vancouver Island, Canada" |
| Author(s): | Fraser JA; Subaran RL; Nichols CB; Heitman J; |
| Address: | "Departments of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina 27710, USA" |
| DOI: | 10.1128/EC.2.5.1036-1045.2003 |
| ISSN/ISBN: | 1535-9778 (Print) 1535-9786 (Electronic) 1535-9786 (Linking) |
| Abstract: | "Cryptococcus neoformans is a human fungal pathogen that exists as three distinct varieties or sibling species: the predominantly opportunistic pathogens C. neoformans var. neoformans (serotype D) and C. neoformans var. grubii (serotype A) and the primary pathogen C. neoformans var. gattii (serotypes B and C). While serotypes A and D are cosmopolitan, serotypes B and C are typically restricted to tropical regions. However, serotype B isolates of C. neoformans var. gattii have recently caused an outbreak on Vancouver Island in Canada, highlighting the threat of this fungus and its capacity to infect immunocompetent individuals. Here we report a large-scale analysis of the mating abilities of serotype B and C isolates from diverse sources and identify unusual strains that mate robustly and are suitable for further genetic analysis. Unlike most isolates, which are of both the a and alpha mating types but are predominantly sterile, the majority of the Vancouver outbreak strains are exclusively of the alpha mating type and the majority are fertile. In an effort to enhance mating of these isolates, we identified and disrupted the CRG1 gene encoding the GTPase-activating protein involved in attenuating pheromone response. crg1 mutations dramatically increased mating efficiency and enabled mating with otherwise sterile isolates. Our studies provide a genetic and molecular foundation for further studies of this primary pathogen and reveal that the Vancouver Island outbreak may be attributable to a recent recombination event" |
| Keywords: | "Biolistics Canada/epidemiology Crosses, Genetic Cryptococcosis/epidemiology Cryptococcus neoformans/classification/genetics/*growth & development Disease Outbreaks Fungal Proteins/genetics/physiology GTPase-Activating Proteins/genetics/*physiology Gene De;" |
| Notes: | "MedlineFraser, James A Subaran, Ryan L Nichols, Connie B Heitman, Joseph eng P01 AI044975/AI/NIAID NIH HHS/ R01 AI050113/AI/NIAID NIH HHS/ P01 AI44975/AI/NIAID NIH HHS/ R01 AI50113/AI/NIAID NIH HHS/ Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. 2003/10/14 Eukaryot Cell. 2003 Oct; 2(5):1036-45. doi: 10.1128/EC.2.5.1036-1045.2003" |
