Insertional mutagenesis enables cleistothecial formation in a non-mating strain of <Emphasis Type="Italic">Histoplasma capsulatum</Emphasis>

Background  

Histoplasma capsulatum is a pathogenic ascomycete fungus that rapidly loses mating ability in culture. Loss of mating ability, as well as the organism's low rate of targeted gene replacement, limits techniques available for genetic studies in H. capsulatum. Understanding molecular mechanisms regulating mating in this organism may allow us to reverse or prevent loss of mating in H. capsulatum strains, introducing a variety of classical genetics techniques to the field. We generated a strain, UC1, by insertional mutagenesis of the laboratory strain G217B, and found that UC1 acquired the ability to form mating structures called cleistothecia. The aim of this study was to determine the mechanism by which UC1 gained the ability to form cleistothecia. We also present initial studies demonstrating that UC1 can be used as a tool to determine molecular correlates of mating in H. capsulatum.