
Full text loading...
Evolution of a Mating System Uniquely Dependent upon Switching and Pathogenesis in Candida albicans, Page 1 of 2
< Previous page Next page > /docserver/preview/fulltext/10.1128/9781555815639/9781555814144_Chap19-1.gif /docserver/preview/fulltext/10.1128/9781555815639/9781555814144_Chap19-2.gifAbstract:
In 1999, researchers identified in the emerging Candida albicans genome the mating-type locus, and one year later two reports documented cell type-dependent mating. With these discoveries, C. albicans had become a sexual organism, but the sequence of discoveries did not stop there. If switching and the mating process proved to play important roles in biofilm formation and pathogenesis, then there could exist strong selection pressure to maintain them. To test biofilm hypothesis, researchers collected spontaneous mating type-like (MTL)-homozygous offspring from natural a/α strains that exhibited high frequencies of MTL-homozygosis and compared virulence of offspring and parent strains in the murine model for systemic infection in two ways. First, they simply followed the survival curves of outbred mice injected individually with each strain. Second, they coinjected parent and offspring with equal numbers of parent and offspring, and at the time of death or extreme morbidity quantitated the concentration of the two strains in the kidney. In the great majority of cases, the parent was more virulent than the offspring in both tests, supporting their hypothesis for a/α maintenance. The intricate relationships between switching, mating, and pathogenesis in C. albicans have therefore provided not only explanations for some of the unique characteristics of each of the component processes, but insights as well into how the basic biology of an organism is manipulated in the evolution of hostpathogen interactions.