title: The Yak1p kinase controls expression of adhesins and biofilm formation in Candida glabrata in a Sir4p-dependent pathway.
abstract: Biofilm is the predominant type of microbial development in natural environments, and potentially represents a major form of resistance or source of recurrence during host infection. Although a large number of studies have focussed on the genetics of bacterial biofilm formation, very little is known about the genes involved in this type of growth in fungi. A genetic screen for Candida glabrata Biofilm mutants was performed using a 96-well plate model of biofilm formation. Study of the isolated mutant strains allowed the identification of four genes involved in biofilm formation (RIF1, SIR4, EPA6 and YAK1). Epa6p is a newly identified adhesin required for biofilm formation in this pathogenic yeast. EPA6 and its close paralogue EPA7 are located in subtelomeric regions and their transcription is regulated by Sir4p and Rif1p, two proteins involved in subtelomeric silencing. Biofilm growth conditions induce the transcription of EPA6 and EPA7: this is dependent on the presence of an intact subtelomeric silencing machinery and is independent of the Mpk1p signalling pathway. Finally, the kinase Yak1p is required for expression of both adhesin genes and acts through a subtelomeric silencing machinery-dependent pathway.
authors.affiliation: Unité de Mycologie Moléculaire, INRA USC 2019, Paris, France.
authors.forename: Ismail
authors.initials: I
authors.lastname: Iraqui
authors.forename: Susana
authors.initials: S
authors.lastname: Garcia-Sanchez
authors.forename: Sylvie
authors.initials: S
authors.lastname: Aubert
authors.forename: Françoise
authors.initials: F
authors.lastname: Dromer
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Ghigo
authors.forename: Christophe
authors.initials: C
authors.lastname: d'Enfert
authors.forename: Guilhem
authors.initials: G
authors.lastname: Janbon
mesh_terms: D018441:Biofilms; D041221:Candida glabrata / Q000235:genetics / Q000254:growth & development / Q000502:physiology* / Q000648:ultrastructure; D002448:Cell Adhesion; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D020868:Gene Silencing; D005838:Genotype; D007700:Kinetics; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D016615:Telomere / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: D005656:Fungal Proteins; D011494:Protein Kinases; C500456:Yak1 protein, Candida glabrata