The morphotype heterogeneity in Cryptococcus neoformans

• Both host and environmental signals entail cryptococcal morphotype heterogeneity.
• Diverse morphotypes are coordinated with saprophytic and pathogenic lifestyles.
• Morphotype heterogeneity is fine-tuned by various intercellular signals.

Many environmental fungi have evolved exceptional abilities to overcome host defenses and to cause systemic infections. However, the evolutionary trajectory that gives rise to the remarkable pathogenic traits of otherwise saprophytic species is poorly understood. Recent studies suggest that social behaviors likely enhance fitness and augment virulence in the ubiquitous fungus Cryptococcus neoformans. In this regard, heterogeneity in morphotypes and the ability to switch morphotype offer flexibility and resilience for this fungus in disparate environmental and host niches. Here, we discuss the tradeoffs of different morphotypes, the complex intercellular communications that coordinate the transitions of diverse morphotypes, and how the resulting heterogeneity in morphotype provides a source of fitness.