title: Detection of phytohormones in temperate forest fungi predicts consistent abscisic acid production and a common pathway for cytokinin biosynthesis.
abstract: The phytohormones, abscisic acid and cytokinin, once were thought to be present uniquely in plants, but increasing evidence suggests that these hormones are present in a wide variety of organisms. Few studies have examined fungi for the presence of these "plant" hormones or addressed whether their levels differ based on the nutrition mode of the fungus. This study examined 20 temperate forest fungi of differing nutritional modes (ectomycorrhizal, wood-rotting, saprotrophic). Abscisic acid and cytokinin were present in all fungi sampled; this indicated that the sampled fungi have the capacity to synthesize these two classes of phytohormones. Of the 27 cytokinins analyzed by HPLC-ESI MS/MS, seven were present in all fungi sampled. This suggested the existence of a common cytokinin metabolic pathway in fungi that does not vary among different nutritional modes. Predictions regarding the source of isopentenyl, cis-zeatin and methylthiol CK production stemming from the tRNA degradation pathway among fungi are discussed.
authors.affiliation: Environmental and Life Sciences Graduate Program, Trent University, Peterborough, Ontario, K9J 7B8 Canada erinmorrison@trentu.ca.
authors.forename: Erin N
authors.initials: EN
authors.lastname: Morrison
authors.affiliation: Biology Department, Trent University, Peterborough, Ontario, K9J 7B8 Canada.
authors.forename: Sarah
authors.initials: S
authors.lastname: Knowles
authors.affiliation: Biology Department, Trent University, Peterborough, Ontario, K9J 7B8 Canada.
authors.forename: Allison
authors.initials: A
authors.lastname: Hayward
authors.affiliation: Department of Biology, Western University, London, Ontario, N6A 5B7 Canada.
authors.forename: R Greg
authors.initials: RG
authors.lastname: Thorn
authors.affiliation: Forensic Science Program, Trent University, Peterborough, Ontario, K9J 7B8 Canada.
authors.forename: Barry J
authors.initials: BJ
authors.lastname: Saville
authors.affiliation: Biology Department, Trent University, Peterborough, Ontario, K9J 7B8 Canada.
authors.forename: R J N
authors.initials: RJ
authors.lastname: Emery
mesh_terms: D000040:Abscisic Acid / Q000032:analysis / Q000096:biosynthesis*; D002851:Chromatography, High Pressure Liquid; D003583:Cytokinins / Q000032:analysis / Q000096:biosynthesis*; D065928:Forests; D005658:Fungi / Q000737:chemistry / Q000145:classification / Q000302:isolation & purification / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000032:analysis / Q000096:biosynthesis*; D053719:Tandem Mass Spectrometry; D014197:Trees / Q000382:microbiology*
chemical_list: D003583:Cytokinins; D010937:Plant Growth Regulators; D000040:Abscisic Acid
keywords: abscisic acid; cytokinins; fungi; high performance liquid chromatography-electrospray ionization tandem mass spectrometry; tRNA degradation pathway