title: The ZmASR1 protein influences branched-chain amino acid biosynthesis and maintains kernel yield in maize under water-limited conditions.
abstract: Abscisic acid-, stress-, and ripening-induced (ASR) proteins were first described about 15 years ago as accumulating to high levels during plant developmental processes and in response to diverse stresses. Currently, the effects of ASRs on water deficit tolerance and the ways in which their physiological and biochemical functions lead to this stress tolerance remain poorly understood. Here, we characterized the ASR gene family from maize (Zea mays), which contains nine paralogous genes, and showed that maize ASR1 (ZmASR1) was encoded by one of the most highly expressed paralogs. Ectopic expression of ZmASR1 had a large overall impact on maize yield that was maintained under water-limited stress conditions in the field. Comparative transcriptomic and proteomic analyses of wild-type and ZmASR1-overexpressing leaves led to the identification of three transcripts and 16 proteins up- or down-regulated by ZmASR1. The majority of them were involved in primary and/or cellular metabolic processes, including branched-chain amino acid (BCAA) biosynthesis. Metabolomic and transcript analyses further indicated that ZmASR1-overexpressing plants showed a decrease in BCAA compounds and changes in BCAA-related gene expression in comparison with wild-type plants. Interestingly, within-group correlation matrix analysis revealed a close link between 13 decreased metabolites in ZmASR1-overexpressing leaves, including two BCAAs. Among these 13 metabolites, six were previously shown to be negatively correlated to biomass, suggesting that ZmASR1-dependent regulation of these 13 metabolites might contribute to regulate leaf growth, resulting in improvement in kernel yield.
authors.affiliation: Université Paris-Sud, UMR 320/UMR 8120 Génétique Végétale, F-91190 Gif-sur-Yvette, France.
authors.forename: Laetitia
authors.initials: L
authors.lastname: Virlouvet
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Jacquemot
authors.forename: Denise
authors.initials: D
authors.lastname: Gerentes
authors.forename: Hélène
authors.initials: H
authors.lastname: Corti
authors.forename: Sophie
authors.initials: S
authors.lastname: Bouton
authors.forename: Françoise
authors.initials: F
authors.lastname: Gilard
authors.forename: Benoît
authors.initials: B
authors.lastname: Valot
authors.forename: Jacques
authors.initials: J
authors.lastname: Trouverie
authors.forename: Guillaume
authors.initials: G
authors.lastname: Tcherkez
authors.forename: Matthieu
authors.initials: M
authors.lastname: Falque
authors.forename: Catherine
authors.initials: C
authors.lastname: Damerval
authors.forename: Peter
authors.initials: P
authors.lastname: Rogowsky
authors.forename: Pascual
authors.initials: P
authors.lastname: Perez
authors.forename: Graham
authors.initials: G
authors.lastname: Noctor
authors.forename: Michel
authors.initials: M
authors.lastname: Zivy
authors.forename: Sylvie
authors.initials: S
authors.lastname: Coursol
mesh_terms: D000595:Amino Acid Sequence; D000597:Amino Acids, Branched-Chain / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D005810:Multigene Family; D018515:Plant Leaves / Q000502:physiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D040901:Proteomics; D012639:Seeds / Q000254:growth & development*; D013312:Stress, Physiological; D014867:Water; D003313:Zea mays / Q000235:genetics
chemical_list: D000597:Amino Acids, Branched-Chain; D010940:Plant Proteins; D014867:Water