Biosciences Research Seminar - A Yeast for All Seasons: What can investigations of genome plasticity teach us about the essential nature of a human fungal pathogen?

Cryptococcus neoformans is a human fungal pathogen associated with soil and arboreal environments that, when inhaled, disseminates from the lung and causes lethal meningitis. While in the lung, and upon exposure to bacteria, this haploid yeast converts to large polyploid titan cells that can themselves produce aneuploid daughter cells. This large scale change in ploidy suggests a high degree of genome plasticity on the part of the fungus and is a major driver of drug resistance. However, the molecular mechanisms underpinning these changes remain unknown. In this talk, I will discuss three ways my group has sought to understand the switch to titans: What environmental signals trigger this switch, how does the host environment add to and influence the switch, and what can studying the capacity of clinical isolates to undergo these changes tell us both about pathogenicity and about fungal adaptation to environmental challenges?