title: Functional characterization and developmental expression profiling of gibberellin signalling components in Vitis vinifera.
abstract: Gibberellins (GAs) regulate numerous developmental processes in grapevine (Vitis vinifera) such as rachis elongation, fruit set, and fruitlet abscission. The ability of GA to promote berry enlargement has led to its indispensable use in the sternospermocarpic ('seedless') table grape industry worldwide. However, apart from VvGAI1 (VvDELLA1), which regulates internode elongation and fruitfulness, but not berry size of seeded cultivars, little was known about GA signalling in grapevine. We have identified and characterized two additional DELLAs (VvDELLA2 and VvDELLA3), two GA receptors (VvGID1a and VvGID1b), and two GA-specific F-box proteins (VvSLY1a and VvSLY1b), in cv. Thompson seedless. With the exception of VvDELLA3-VvGID1b, all VvDELLAs interacted with the VvGID1s in a GA-dependent manner in yeast two-hybrid assays. Additionally, expression of these grape genes in corresponding Arabidopsis mutants confirmed their functions in planta. Spatiotemporal analysis of VvDELLAs showed that both VvDELLA1 and VvDELLA2 are abundant in most tissues, except in developing fruit where VvDELLA2 is uniquely expressed at high levels, suggesting a key role in fruit development. Our results further suggest that differential organ responses to exogenous GA depend on the levels of VvDELLA proteins and endogenous bioactive GAs. Understanding this interaction will allow better manipulation of GA signalling in grapevine.
authors.affiliation: Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel Institute of Plant Sciences and Genetics in Agriculture, The Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
authors.forename: Atiako Kwame
authors.initials: AK
authors.lastname: Acheampong
authors.affiliation: Department of Biology, Duke University, Durham, North Carolina 27708, USA.
authors.forename: Jianhong
authors.initials: J
authors.lastname: Hu
authors.affiliation: Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel.
authors.forename: Ariel
authors.initials: A
authors.lastname: Rotman
authors.affiliation: Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel Institute of Plant Sciences and Genetics in Agriculture, The Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
authors.forename: Chuanlin
authors.initials: C
authors.lastname: Zheng
authors.affiliation: Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel.
authors.forename: Tamar
authors.initials: T
authors.lastname: Halaly
authors.affiliation: RIKEN Plant Science Centre, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Takebayashi
authors.affiliation: RIKEN Plant Science Centre, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Jikumaru
authors.affiliation: RIKEN Plant Science Centre, Yokohama, Kanagawa 230-0045, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kamiya
authors.affiliation: Institute of Postharvest and Food Sciences, Department of Postharvest Science of Fresh Produce, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel.
authors.forename: Amnon
authors.initials: A
authors.lastname: Lichter
authors.affiliation: Department of Biology, Duke University, Durham, North Carolina 27708, USA.
authors.forename: Tai-Ping
authors.initials: TP
authors.lastname: Sun
authors.affiliation: Institute of Plant Sciences, Department of Fruit Tree Sciences, Agricultural Research Organization, Volcani Centre, Bet Dagan 50250, Israel vettior@agri.gov.il.
authors.forename: Etti
authors.initials: E
authors.lastname: Or
mesh_terms: D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D005875:Gibberellins / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction; D027843:Vitis / Q000235:genetics* / Q000254:growth & development* / Q000378:metabolism
chemical_list: D005875:Gibberellins; D010937:Plant Growth Regulators; D010940:Plant Proteins
keywords: F-box proteins; GA receptors; VvDELLA proteins.; gibberellin signalling; gibberellins (GAs); grapevine (Vitis vinifera)