A conserved stress-activated protein kinase regulates a core stress response in the human pathogen Candida albicans.
Previous work has implicated the Hog1 stress-activated protein kinase (SAPK) in osmotic and oxidative stress responses in the human pathogen Candida albicans. In this study, we have characterized the role of Hog1 in mediating these and other stress responses in C. albicans. We provide evidence that a SAPK-dependent core stress response exists in this pathogen. The Hog1 SAPK is phosphorylated and it accumulates in the nucleus in response to diverse stress conditions. In addition, we have identified Hog1-regulated genes that are induced in response to stress conditions that activate Hog1. These analyses reveal both activator and repressor functions for the Hog1 SAPK. Our results also demonstrate that stress cross-protection, a classical hallmark of the core stress response, occurs in C. albicans between stresses that activate the Hog1 SAPK. Importantly, we find that the core stress response in C. albicans has adapted to the environmental niche of this human pathogen. This niche specificity is reflected by the specific environmental conditions that drive the Hog1-regulated core stress response in C. albicans and by differences in the molecular circuitry that control this response.
Smith
Deborah A
DA
School of Cell and Molecular Biosciences, University of Newcastle upon Tyne, Newcastle upon Tyne NE2 4HH, United Kingdom.
Nicholls
Susan
S
Morgan
Brian A
BA
Brown
Alistair J P
AJ
Quinn
Janet
J
D001483:Base Sequence; D002176:Candida albicans / Q000201:enzymology* / Q000235:genetics / Q000472:pathogenicity; D002467:Cell Nucleus / Q000201:enzymology; D004271:DNA, Fungal / Q000235:genetics; D004789:Enzyme Activation; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D005816:Genetic Complementation Test; D006801:Humans; D020935:MAP Kinase Signaling System; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000378:metabolism*; D008954:Models, Biological; D008969:Molecular Sequence Data; D009997:Osmotic Pressure; D018384:Oxidative Stress; D010641:Phenotype; D010766:Phosphorylation; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D012568:Schizosaccharomyces / Q000201:enzymology / Q000235:genetics; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism; D013045:Species Specificity
D004271:DNA, Fungal; D029702:Schizosaccharomyces pombe Proteins; D020928:Mitogen-Activated Protein Kinases; C095409:sty1 protein, S pombe