title: Sep7 is essential to modify septin ring dynamics and inhibit cell separation during Candida albicans hyphal growth.
abstract: When Candida albicans yeast cells receive the appropriate stimulus, they switch to hyphal growth, characterized by continuous apical elongation and the inhibition of cell separation. The molecular basis of this inhibition is poorly known, despite its crucial importance for hyphal development. In C. albicans, septins are important for hypha formation and virulence. Here, we used fluorescence recovery after photobleaching analysis to characterize the dynamics of septin rings during yeast and hyphal growth. On hyphal induction, septin rings are converted to a hyphal-specific state, characterized by the presence of a frozen core formed by Sep7/Shs1, Cdc3 and Cdc12, whereas Cdc10 is highly dynamic and oscillates between the ring and the cytoplasm. Conversion of septin rings to the hyphal-specific state inhibits the translocation of Cdc14 phosphatase, which controls cell separation, to the hyphal septum. Modification of septin ring dynamics during hyphal growth is dependent on Sep7 and the hyphal-specific cyclin Hgc1, which partially controls Sep7 phosphorylation status and protein levels. Our results reveal a link between the cell cycle machinery and septin cytoskeleton dynamics, which inhibits cell separation in the filaments and is essential for hyphal morphogenesis.
authors.affiliation: Departmento Microbiología y Genética, Instituto de Microbiología Bioquímica, Universidad de Salamanca/Consejo Superior de Investigaciones Científicas, 37007 Salamanca, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: González-Novo
authors.forename: Jaime
authors.initials: J
authors.lastname: Correa-Bordes
authors.forename: Leticia
authors.initials: L
authors.lastname: Labrador
authors.forename: Miguel
authors.initials: M
authors.lastname: Sánchez
authors.forename: Carlos R
authors.initials: CR
authors.lastname: Vázquez de Aldana
authors.forename: Javier
authors.initials: J
authors.lastname: Jiménez
mesh_terms: D002176:Candida albicans / Q000166:cytology / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D002453:Cell Cycle; D018797:Cell Cycle Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D003599:Cytoskeleton / Q000378:metabolism; D036681:Fluorescence Recovery After Photobleaching; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005800:Genes, Fungal; D025301:Hyphae / Q000254:growth & development / Q000378:metabolism; D046912:Multiprotein Complexes; D009154:Mutation; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics / Q000378:metabolism; D010766:Phosphorylation; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D013045:Species Specificity
chemical_list: D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D046912:Multiprotein Complexes; D010744:Phosphoric Monoester Hydrolases; D019204:GTP-Binding Proteins