title: Nostopeptolide plays a governing role during cellular differentiation of the symbiotic cyanobacterium Nostoc punctiforme.
abstract: Nostoc punctiforme is a versatile cyanobacterium that can live either independently or in symbiosis with plants from distinct taxa. Chemical cues from plants and N. punctiforme were shown to stimulate or repress, respectively, the differentiation of infectious motile filaments known as hormogonia. We have used a polyketide synthase mutant that accumulates an elevated amount of hormogonia as a tool to understand the effect of secondary metabolites on cellular differentiation of N. punctiforme. Applying MALDI imaging to illustrate the reprogramming of the secondary metabolome, nostopeptolides were identified as the predominant difference in the pks2(-) mutant secretome. Subsequent differentiation assays and visualization of cell-type-specific expression of nostopeptolides via a transcriptional reporter strain provided evidence for a multifaceted role of nostopeptolides, either as an autogenic hormogonium-repressing factor or as a chemoattractant, depending on its extracellular concentration. Although nostopeptolide is constitutively expressed in the free-living state, secreted levels dynamically change before, during, and after the hormogonium differentiation phase. The metabolite was found to be strictly down-regulated in symbiosis with Gunnera manicata and Blasia pusilla, whereas other metabolites are up-regulated, as demonstrated via MALDI imaging, suggesting plants modulate the fine-balanced cross-talk network of secondary metabolites within N. punctiforme.
authors.affiliation: Faculty of Biosciences, Fisheries and Economics, Department of Arctic and Marine Biology, Molecular Environments Group, University of Tromsø, 9037 Tromsø, Norway;
authors.forename: Anton
authors.initials: A
authors.lastname: Liaimer
authors.affiliation: Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, 07745 Jena, Germany; and.
authors.forename: Eric J N
authors.initials: EJ
authors.lastname: Helfrich
authors.affiliation: Institute for Biochemistry and Biology, Department of Microbiology, University of Potsdam, 14476 Potsdam-Golm, Germany.
authors.forename: Katrin
authors.initials: K
authors.lastname: Hinrichs
authors.affiliation: Institute for Biochemistry and Biology, Department of Microbiology, University of Potsdam, 14476 Potsdam-Golm, Germany.
authors.forename: Arthur
authors.initials: A
authors.lastname: Guljamow
authors.affiliation: Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, 07745 Jena, Germany; and.
authors.forename: Keishi
authors.initials: K
authors.lastname: Ishida
authors.affiliation: Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, 07745 Jena, Germany; and.
authors.forename: Christian
authors.initials: C
authors.lastname: Hertweck
authors.affiliation: Institute for Biochemistry and Biology, Department of Microbiology, University of Potsdam, 14476 Potsdam-Golm, Germany editt@uni-potsdam.de.
authors.forename: Elke
authors.initials: E
authors.lastname: Dittmann
mesh_terms: D002454:Cell Differentiation / Q000502:physiology*; D022081:Cell Surface Extensions / Q000502:physiology*; D002851:Chromatography, High Pressure Liquid; D019669:Embryophyta / Q000382:microbiology / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D019684:Magnoliopsida / Q000382:microbiology / Q000502:physiology; D015394:Molecular Structure; D046937:Nostoc / Q000378:metabolism / Q000502:physiology*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D018521:Plant Physiological Phenomena; D013045:Species Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013559:Symbiosis / Q000502:physiology*
chemical_list: D010455:Peptides
keywords: MALDI imaging; cell differentiation; nonribosomal peptide; signaling; symbiosis