D. Kadosh et Ad. Johnson, Rfg1, a protein related to the Saccharomyces cerevisiae hypoxic regulator Rox1, controls filamentous growth and virulence in Candida albicans, MOL CELL B, 21(7), 2001, pp. 2496-2505
Candida albicans, the major fungal pathogen in humans, can undergo a revers
ible transition from ellipsoidal single cells (blastospores) to filaments c
omposed of elongated cells attached end to end. This transition is thought
to allow for rapid colonization of host tissues, facilitating the spread of
infection, Here, we report the identification of Rfg1, a transcriptional r
egulator that controls filamentous growth of C. albicans in an environment-
dependent manner. Rfg1 is important for virulence of C. albicans in a mouse
model and is shown to control a number of genes that have been implicated
in this process. The closest relative to Rfg1 in Saccharomyces cerevisiae i
s Rox1, a key repressor of hypoxic genes. However, Rfg1 does not appear to
play a role in the regulation of hypoxic genes in C. albicans, These result
s demonstrate that a regulatory protein that controls the hypoxic response
in S. cerevisiae controls filamentous growth and virulence in C. albicans.
The observations described in this paper raise new and intriguing questions
about the evolutionary relationship between these processes.