title: Yeast adaptation to 2,4-dichlorophenoxyacetic acid involves increased membrane fatty acid saturation degree and decreased OLE1 transcription.
abstract: Yeast cells adapted to the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) exhibit a plasma membrane less susceptible to 2,4-D-induced disruption and are more tolerant than unadapted cells to lethal concentrations of the herbicide. These cells, adapted to grow in the presence of increasing concentrations of 2,4-D, were found to exhibit a dose-dependent increase of the saturation degree of membrane fatty acids, associated to the higher percentage of stearic (C(18:0)) and palmitic (C(16:0)) acids, and to the decreased percentage of palmitoleic (Delta9-cisC(16:1)) and oleic (Delta9-cisC(18:1)) acids. The decreased transcription of the OLE1 gene (encoding the Delta9 fatty acid desaturase that catalyses the conversion of palmitic and stearic acids to palmitoleic and oleic acids, respectively) registered in 2,4-D adapted cells suggests that yeast adaptation to the herbicide involves the enhancement of the ratio of saturated (C(16:0) and C(18:0)) to monounsaturated (C(16:1) and C(18:1)) membrane fatty acids through a reduced OLE1 expression.
authors.affiliation: Biological Sciences Research Group, Centre for Biological and Chemical Engineering, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisbon, Portugal.
authors.forename: Cristina A
authors.initials: CA
authors.lastname: Viegas
authors.forename: M Guadalupe
authors.initials: MG
authors.lastname: Cabral
authors.forename: Miguel C
authors.initials: MC
authors.lastname: Teixeira
authors.forename: Grit
authors.initials: G
authors.lastname: Neumann
authors.forename: Hermann J
authors.initials: HJ
authors.lastname: Heipieper
authors.forename: Isabel
authors.initials: I
authors.lastname: Sá-Correia
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000494:pharmacology*; D000222:Adaptation, Physiological / Q000187:drug effects*; D001483:Base Sequence; D002462:Cell Membrane / Q000378:metabolism; D002463:Cell Membrane Permeability / Q000187:drug effects; D017931:DNA Primers; D044943:Fatty Acid Desaturases / Q000235:genetics*; D005227:Fatty Acids / Q000378:metabolism*; D013230:Stearoyl-CoA Desaturase; D014158:Transcription, Genetic / Q000502:physiology*
chemical_list: D017931:DNA Primers; D005227:Fatty Acids; D015084:2,4-Dichlorophenoxyacetic Acid; D044943:Fatty Acid Desaturases; D013230:Stearoyl-CoA Desaturase; C029627:delta-9 fatty acid desaturase