title: New "haploid biofilm model" unravels IRA2 as a novel regulator of Candida albicans biofilm formation.
abstract: Clinical isolates of the fungal human pathogen Candida albicans are invariably diploid and heterozygous, impeding genetic study. Recent isolation of C. albicans haploids opens opportunities to apply technologies unfeasible in diploids. However, doubts remain on whether the haploids, derived from chromosome loss, can represent the diploids. Here, we use C. albicans haploids to investigate biofilm, a key virulence attribute. We conducted the first comprehensive characterization of biofilm formation of the haploids in comparison with the diploids. We demonstrate that the haploids form biofilms with essentially the same characteristics as the diploids. Screening a haploid mutant library has uncovered novel GTPase-related genes as biofilm regulators, including IRA2 that encodes an activator of the Ras GTPase. IRA2-deletion mutants develop poorly constructed biofilm in both haploid and diploid C. albicans. Our results demonstrate that the haploids are a valid model for C. albicans biofilm research and a powerful tool for uncovering novel regulators.
authors.affiliation: Oral Sciences, Faculty of Dentistry, National University of Singapore.
authors.forename: Chaminda Jayampath
authors.initials: CJ
authors.lastname: Seneviratne
authors.affiliation: Institute of Molecular &Cell Biology, Agency for Science, Technology and Research, Proteos, Singapore.
authors.forename: Guisheng
authors.initials: G
authors.lastname: Zeng
authors.affiliation: Oral Sciences, Faculty of Dentistry, National University of Singapore.
authors.forename: Thuyen
authors.initials: T
authors.lastname: Truong
authors.affiliation: Oral Sciences, Faculty of Dentistry, National University of Singapore.
authors.forename: Sarah
authors.initials: S
authors.lastname: Sze
authors.affiliation: Faculty of Dentistry, The University of Hong Kong, Hong Kong.
authors.forename: Wah
authors.initials: W
authors.lastname: Wong
authors.affiliation: 1] Faculty of Dentistry, The University of Hong Kong, Hong Kong [2] School of Dentistry, Queensland University, Australia.
authors.forename: Lakshman
authors.initials: L
authors.lastname: Samaranayake
authors.affiliation: Institute of Molecular &Cell Biology, Agency for Science, Technology and Research, Proteos, Singapore.
authors.forename: Fong Yee
authors.initials: FY
authors.lastname: Chan
authors.affiliation: Institute of Molecular &Cell Biology, Agency for Science, Technology and Research, Proteos, Singapore.
authors.forename: Yan-Ming
authors.initials: YM
authors.lastname: Wang
authors.affiliation: Institute of Molecular &Cell Biology, Agency for Science, Technology and Research, Proteos, Singapore.
authors.forename: Haitao
authors.initials: H
authors.lastname: Wang
authors.affiliation: Institute of Molecular &Cell Biology, Agency for Science, Technology and Research, Proteos, Singapore.
authors.forename: Jiaxin
authors.initials: J
authors.lastname: Gao
authors.affiliation: 1] Institute of Molecular &Cell Biology, Agency for Science, Technology and Research, Proteos, Singapore [2] Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
authors.forename: Yue
authors.initials: Y
authors.lastname: Wang
mesh_terms: D018441:Biofilms / Q000254:growth & development*; D002176:Candida albicans / Q000145:classification* / Q000166:cytology / Q000502:physiology*; D049109:Cell Proliferation / Q000502:physiology; D020690:GTPase-Activating Proteins / Q000378:metabolism*; D006238:Haploidy; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D020690:GTPase-Activating Proteins; C064960:IRA2 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins