title: Regulatory role of the PKA pathway in dimorphism and mating in Yarrowia lipolytica.
abstract: Previous studies on the dimorphic transition of Yarrowia lipolytica suggested opposite roles for MAPK and PKA pathways in this phenomenon. To obtain conclusive evidences for these opposite roles we isolated and disrupted the unique gene encoding the Pka catalytic subunit (TPK1). TPK1 was regulated only at the post-transcriptional level, with Pka activity increasing during yeast-like growth. tpk1 null mutants were viable and without growth defects, but more sensitive to different stress conditions. Deltatpk1 mutants were mating-deficient, and grew constitutively in the mycelial form, whereas Deltaste11 (Mapkkk-less)/Deltatpk1 double mutants grew in the yeast form, indicating that this is the default growth pattern of the fungus. Our data confirm that MAPK and PKA pathways operate in opposition during the dimorphic behavior of Y. lipolytica, but synergic in mating. These data stress the idea that in different fungi both signal transduction systems may operate distinctly or even be antagonistic or synergic in the coordination of cell responses to different stimuli.
authors.affiliation: Departamento de Ingeniería Genética, Unidad Irapuato, Centro de Investigación y de Estudios Avanzados del IPN., Irapuato, Gto., Mexico.
authors.forename: José A
authors.initials: JA
authors.lastname: Cervantes-Chávez
authors.forename: Florencia
authors.initials: F
authors.lastname: Kronberg
authors.forename: Susana
authors.initials: S
authors.lastname: Passeron
authors.forename: José
authors.initials: J
authors.lastname: Ruiz-Herrera
mesh_terms: D000818:Animals; D054751:Cyclic AMP-Dependent Protein Kinase Catalytic Subunits / Q000235:genetics; D017868:Cyclic AMP-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism*; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics; D017353:Gene Deletion; D015966:Gene Expression Regulation, Fungal; D020930:MAP Kinase Kinase Kinases / Q000235:genetics; D008969:Molecular Sequence Data; D025282:Mycelium / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins; D017422:Sequence Analysis, DNA; D015398:Signal Transduction; D025062:Yarrowia / Q000166:cytology* / Q000254:growth & development / Q000502:physiology*; D015003:Yeasts / Q000254:growth & development
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D029701:Saccharomyces cerevisiae Proteins; D054751:Cyclic AMP-Dependent Protein Kinase Catalytic Subunits; D017868:Cyclic AMP-Dependent Protein Kinases; D020930:MAP Kinase Kinase Kinases; C067018:Ste11 protein, S cerevisiae