title: HvDep1 Is a Positive Regulator of Culm Elongation and Grain Size in Barley and Impacts Yield in an Environment-Dependent Manner.
abstract: Heterotrimeric G proteins are intracellular membrane-attached signal transducers involved in various cellular processes in both plants and animals. They consist of three subunits denoted as α, β and γ. The γ-subunits of the so-called AGG3 type, which comprise a transmembrane domain, are exclusively found in plants. In model species, these proteins have been shown to participate in the control of plant height, branching and seed size and could therefore impact the harvestable yield of various crop plants. Whether AGG3-type γ-subunits influence yield in temperate cereals like barley and wheat remains unknown. Using a transgenic complementation approach, we show here that the Scottish malting barley cultivar (cv.) Golden Promise carries a loss-of-function mutation in HvDep1, an AGG3-type subunit encoding gene that positively regulates culm elongation and seed size in barley. Somewhat intriguingly, agronomic field data collected over a 12-year period reveals that the HvDep1 loss-of-function mutation in cv. Golden Promise has the potential to confer either a significant increase or decrease in harvestable yield depending on the environment. Our results confirm the role of AGG3-type subunit-encoding genes in shaping plant architecture, but interestingly also indicate that the impact HvDep1 has on yield in barley is both genotypically and environmentally sensitive. This may explain why widespread exploitation of variation in AGG3-type subunit-encoding genes has not occurred in temperate cereals while in rice the DEP1 locus is widely exploited to improve harvestable yield.
authors.affiliation: Carlsberg Research Laboratory, Copenhagen, Denmark.
authors.forename: Toni
authors.initials: T
authors.lastname: Wendt
authors.affiliation: Department of Molecular Biology and Genetics, Faculty of Science and Technology, Aarhus University, Slagelse, Denmark.
authors.forename: Inger
authors.initials: I
authors.lastname: Holme
authors.affiliation: Carlsberg Research Laboratory, Copenhagen, Denmark.
authors.forename: Christoph
authors.initials: C
authors.lastname: Dockter
authors.affiliation: Carlsberg Research Laboratory, Copenhagen, Denmark.
authors.forename: Aileen
authors.initials: A
authors.lastname: Preuß
authors.affiliation: James Hutton Institute, Invergowrie, Dundee, United Kingdom.
authors.forename: William
authors.initials: W
authors.lastname: Thomas
authors.affiliation: James Hutton Institute, Invergowrie, Dundee, United Kingdom.
authors.forename: Arnis
authors.identifier: http://orcid.org/0000-0003-3663-2694
authors.initials: A
authors.lastname: Druka
authors.affiliation: James Hutton Institute, Invergowrie, Dundee, United Kingdom.|Division of Plant Sciences, The University of Dundee, Invergowrie, Dundee, United Kingdom.
authors.forename: Robbie
authors.initials: R
authors.lastname: Waugh
authors.affiliation: Department of Biology, Lund University, Lund, Sweden.
authors.forename: Mats
authors.identifier: http://orcid.org/0000-0002-0168-9968
authors.initials: M
authors.lastname: Hansson
authors.affiliation: Carlsberg Research Laboratory, Copenhagen, Denmark.
authors.forename: Ilka
authors.initials: I
authors.lastname: Braumann
mesh_terms: D002874:Chromosome Mapping; D044388:GTP-Binding Protein gamma Subunits / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D056726:Genetic Association Studies; D005838:Genotype; D001467:Hordeum / Q000235:genetics* / Q000254:growth & development; D009154:Mutation; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D030821:Plants, Genetically Modified / Q000033:anatomy & histology / Q000254:growth & development; D040641:Quantitative Trait Loci; D012639:Seeds / Q000033:anatomy & histology / Q000235:genetics / Q000254:growth & development; D015398:Signal Transduction
chemical_list: D044388:GTP-Binding Protein gamma Subunits; D010940:Plant Proteins