title: The Arabidopsis N-Acetylornithine Deacetylase Controls Ornithine Biosynthesis via a Linear Pathway with Downstream Effects on Polyamine Levels.
abstract: Arabidopsis thaliana At4g17830 codes for a protein showing sequence similarity with the Escherichia coli N-acetylornithine deacetylase (EcArgE), an enzyme implicated in the linear ornithine (Orn) biosynthetic pathway. In plants, N-acetylornithine deacetylase (NAOD) activity has yet to be demonstrated; however, At4g17830-silenced and mutant (atnaod) plants display an impaired reproductive phenotype and altered foliar levels of Orn and polyamines (PAs). Here, we showed the direct connection between At4g17830 function and Orn biosynthesis, demonstrating biochemically that At4g17830 codes for a NAOD. These results are the first experimental proof that Orn can be produced in Arabidopsis via a linear pathway. In this study, to identify the role of AtNAOD in reproductive organs, we carried out a transcriptomic analysis on atnaod mutant and wild-type flowers. In the atnaod mutant, the most relevant effects were the reduced expression of cysteine-rich peptide-coding genes, known to regulate male-female cross-talk during reproduction, and variation in the expression of genes involved in nitrogen:carbon (N:C) status. The atnaod mutant also exhibited increased levels of sucrose and altered sensitivity to glucose. We hypothesize that AtNAOD participates in Orn and PA homeostasis, contributing to maintain an optimal N:C balance during reproductive development.
authors.affiliation: Department of Biotechnology, University of Verona, Verona, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Molesini
authors.affiliation: Department of Biotechnology, University of Verona, Verona, Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Zanzoni
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di Ricerca per l'Orticoltura, Pontecagnano-Faiano (Salerno), Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Mennella
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Centro di Ricerca per l'Orticoltura, Pontecagnano-Faiano (Salerno), Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Francese
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Unità di ricerca per l'Orticoltura (ORL), Montanaso Lombardo (Lodi), Italy.
authors.forename: Alessia
authors.initials: A
authors.lastname: Losa
authors.affiliation: Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria, Unità di ricerca per l'Orticoltura (ORL), Montanaso Lombardo (Lodi), Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: L Rotino
authors.affiliation: Department of Biotechnology, University of Verona, Verona, Italy.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Pandolfini
mesh_terms: D000581:Amidohydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D055162:Biocatalysis; D053898:Biosynthetic Pathways / Q000235:genetics; D004591:Electrophoresis, Polyacrylamide Gel; D035264:Flowers / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling / Q000379:methods; D018506:Gene Expression Regulation, Plant; D006868:Hydrolysis; D007700:Kinetics; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D009154:Mutation; D009952:Ornithine / Q000031:analogs & derivatives / Q000096:biosynthesis* / Q000737:chemistry / Q000378:metabolism; D010802:Phylogeny; D011073:Polyamines / Q000378:metabolism*; D000072417:Protein Domains; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid
chemical_list: D029681:Arabidopsis Proteins; D011073:Polyamines; C021951:N(delta)-acetylornithine; D009952:Ornithine; D000581:Amidohydrolases; C018732:N-acetylornithine deacetylase
keywords: N-Acetylornithine deacetylase; Ornithine; Polyamine; Reproductive development