title: The transmembrane protein Opy2 mediates activation of the Cek1 MAP kinase in Candida albicans.
abstract: MAPK pathways are conserved and complex mechanisms of signaling in eukaryotic cells. These pathways mediate adaptation to different stress conditions by a core kinase cascade that perceives changes in the environment by different upstream elements and mediates adaptation through transcription factors. In the present work, the transmembrane protein Opy2 has been identified and functionally characterized in Candida albicans. This protein is required to trigger Cek1 phosphorylation by different stimuli such as the resumption of growth from stationary phase or the addition of the cell wall disturbing compounds zymolyase and tunicamycin. opy2 mutants display susceptibility to cell wall disturbing compounds like Congo red. However, it does not play a role in the adaptation to high osmolarity or oxidative stress, in close contrast with the situation for the homologous protein in Saccharomyces cerevisiae. The over-expression of Opy2 in a S. cerevisiae opy2ssk1 mutant partially complemented the osmosensitivity on solid medium by a Hog1-independent mechanism as well as the abnormal morphology observed in this mutant under high osmolarity. The electrophoretic pattern of CaOpy2 tagged version in S. cerevisiae suggested similar post-translational modification in both microorganisms. This protein is also involved in pathogenesis as revealed by the fact that opy2 mutants displayed a significantly reduced virulence in the Galleria mellonella model.
authors.affiliation: Departamento de Microbiología II, Universidad Complutense de Madrid, Plaza de Ramón y Cajal s/n, Madrid, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Herrero de Dios
authors.forename: Elvira
authors.initials: E
authors.lastname: Román
authors.forename: Carla
authors.initials: C
authors.lastname: Diez
authors.forename: Rebeca
authors.initials: R
authors.lastname: Alonso-Monge
authors.forename: Jesús
authors.initials: J
authors.lastname: Pla
mesh_terms: D000818:Animals; D000935:Antifungal Agents / Q000633:toxicity; D002176:Candida albicans / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism* / Q000502:physiology; D003224:Congo Red / Q000633:toxicity; D005656:Fungal Proteins / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D055786:Gene Knockout Techniques; D005816:Genetic Complementation Test; D007915:Lepidoptera; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics; D015398:Signal Transduction; D016019:Survival Analysis; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D000935:Antifungal Agents; D005656:Fungal Proteins; D008565:Membrane Proteins; D037521:Virulence Factors; C077339:CEK1 protein, Candida albicans; D003224:Congo Red; D048052:Mitogen-Activated Protein Kinase 3