Efg1 (a member of the APSES family) is an important regulator of hyphal growth and of the white-to-opaque transition in Candida albicans and very closely related species. We show that in Candida parapsilosis Efg1 is a major regulator of a different morphological switch at the colony level, from a concentric to smooth morphology. The rate of switching is at least 20-fold increased in an efg1 kno...

Efg1 is essential for hyphal development in the human pathogen Candida albicans under most conditions. Efg1 is related to basic helix-loop-helix regulators, and therefore most workers presume that Efg1 is a transcription factor. Here we confirm that Efg1 is a DNA binding protein that can interact specifically with the E box.

POSTERS Analysis of sterol regulation in the Saccharomycotina. Many fungal pathogens grow on superficial and in internal sites in infected hosts, regions that have considerably different oxygen levels. A better understanding of the influence of hypoxia (low oxygen) on virulence and pathogenesis may lead to improved treatments against systemic fungal infections. Hypoxia induces filamentation of ...

Cell chain formation is a characteristic of filamentous growth in fungi. How it is regulated developmentally in multimorphic fungi is not known. In Candida albicans, degradation of septa during yeast growth is accomplished by enzymes encoded by Ace2 activated genes expressed in G(1). We found that phosphorylation of a conserved developmental regulator, Efg1, by the cyclin-dependent kinase Cdc28...

Ribosome biogenesis in eukaryotes is a complicated process that involves association and dissociation of numerous assembly factors and snoRNAs. The yeast small ribosomal subunit is first assembled into 90S pre-ribosomes in an ordered and dynamic manner. Efg1 is a protein with no recognizable domain that is associated with early 90S particles. Here, we determine the crystal structure of Efg1 fro...

Chlamydospore formation of the fungal pathogen Candida albicans was found to depend on the Efg1 protein, which regulates the yeast-hyphal transition. Isogenic mutants lacking EFG1 or encoding T206A and T206E variants did not differentiate chlamydospores, while cek1, cph1, or tpk2 mutations had no effect. Furthermore, filamentation of efg1 cph1 double mutants in microaerophilic conditions sugges...

Heritable epigenetic changes underlie the ability of cells to differentiate into distinct cell types. Here, we demonstrate that the fungal pathogen Candida tropicalis exhibits multipotency, undergoing stochastic and reversible switching between three cellular states. The three cell states exhibit unique cellular morphologies, growth rates, and global gene expression profiles. Genetic analysis i...

In Candida albicans the transcription factor Efg1, which is differentially expressed in the white phase of the white-opaque transition, is essential for expression of the white phenotype. It is one of six transcription factors included in a proposed interactive transcription network regulating white-opaque switching and maintenance of the alternative phenotypes. Ten sites were identified in the...

Filamentous growth is an important virulence trait of the human pathogenic fungi within the genus Candida, and the greater propensity of C. albicans to form hyphae has been proposed to account for the greater virulence of this species relative to the less pathogenic species C. dubliniensis. In this meta-analysis, we compare the transcriptional response of C. dubliniensis and C. albicans to the ...