title: Discovery of the gray phenotype and white-gray-opaque tristable phenotypic transitions in Candida dubliniensis.
abstract: Candida dubliniensis is closely related to Candida albicans, a major causative agent of candidiasis, and is primarily associated with oral colonization and infection in human immunodeficiency virus (HIV)-positive patients. Despite the high similarity of genomic and phenotypic features between the 2 species, C. dubliniensis is much less virulent and less prevalent than C. albicans. The ability to change morphological phenotypes is a striking feature of Candida species and is linked to virulence. In this study, we report a novel phenotype, the gray phenotype, in C. dubliniensis. Together with the previously reported white and opaque cell types, the gray phenotype forms a tristable phenotypic switching system in C. dubliniensis that is similar to the white-gray-opaque tristable switching system in C. albicans. Gray cells of C. dubliniensis are similar to their counterparts in C. albicans in terms of several biological aspects including cellular morphology, mating competence, and genetic regulatory mechanisms. However, the gray phenotypes of the 2 species have some distinguishing features. For example, the secreted aspartyl protease (Sap) activity is induced by bovine serum albumin (BSA) in gray cells of C. albicans, but not in gray cells of C. dubliniensis. Taken together, our results demonstrate that the biological features and regulatory mechanisms of white-gray-opaque tristable transitions are largely conserved in the 2 pathogenic Candida species.
authors.affiliation: a State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences , Beijing , China.|b University of Chinese Academy of Sciences , Beijing , China.
authors.forename: Huizhen
authors.initials: H
authors.lastname: Yue
authors.affiliation: a State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences , Beijing , China.|c Department of Dermatology , Peking University People's Hospital , Beijing , China.
authors.forename: Jian
authors.initials: J
authors.lastname: Hu
authors.affiliation: a State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences , Beijing , China.
authors.forename: Guobo
authors.initials: G
authors.lastname: Guan
authors.affiliation: a State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences , Beijing , China.
authors.forename: Li
authors.initials: L
authors.lastname: Tao
authors.affiliation: a State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences , Beijing , China.
authors.forename: Han
authors.initials: H
authors.lastname: Du
authors.affiliation: c Department of Dermatology , Peking University People's Hospital , Beijing , China.
authors.forename: Houmin
authors.initials: H
authors.lastname: Li
authors.affiliation: a State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences , Beijing , China.
authors.forename: Guanghua
authors.initials: G
authors.lastname: Huang
mesh_terms: D057055:Aspartic Acid Proteases / Q000378:metabolism; D002175:Candida / Q000187:drug effects / Q000201:enzymology / Q000235:genetics* / Q000472:pathogenicity; D002176:Candida albicans / Q000235:genetics* / Q000472:pathogenicity; D002177:Candidiasis / Q000382:microbiology; D015966:Gene Expression Regulation, Fungal; D006801:Humans; D010641:Phenotype; D010802:Phylogeny; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D014774:Virulence
chemical_list: D012710:Serum Albumin, Bovine; D057055:Aspartic Acid Proteases
keywords: Candida dubliniensis; Efg1; Wor1; pathogenesis; phenotypic switching