title: Gladiolus hybridus ABSCISIC ACID INSENSITIVE 5 (GhABI5) is an important transcription factor in ABA signaling that can enhance Gladiolus corm dormancy and Arabidopsis seed dormancy.
abstract: The phytohormone abscisic acid (ABA) regulates plant development and is crucial for abiotic stress response. In this study, cold storage contributes to reducing endogenous ABA content, resulting in dormancy breaking of Gladiolus. The ABA inhibitor fluridone also promotes germination, suggesting that ABA is an important hormone that regulates corm dormancy. Here, we report the identification and functional characterization of the Gladiolus ABI5 homolog (GhABI5), which is a basic leucine zipper motif transcriptional factor (TF). GhABI5 is expressed in dormant vegetative organs (corm, cormel, and stolon) as well as in reproductive organs (stamen), and it is up-regulated by ABA or drought. Complementation analysis reveals that GhABI5 rescues the ABA insensitivity of abi5-3 during seed germination and induces the expression of downstream ABA response genes in Arabidopsis thaliana (EM1, EM6, and RD29B). Down-regulation of GhABI5 in dormant cormels via virus induced gene silence promotes sprouting and reduces the expression of downstream genes (GhLEA and GhRD29B). The results of this study reveal that GhABI5 regulates bud dormancy (vegetative organ) in Gladiolus in addition to its well-studied function in Arabidopsis seeds (reproductive organ).
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University Beijing, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Wu
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University Beijing, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Seng
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University Beijing, China.
authors.forename: Juanjuan
authors.initials: J
authors.lastname: Sui
authors.affiliation: Department of Biological Sciences, University of Toronto Toronto, ON, Canada ; Department of Cell and Systems Biology, University of Toronto Toronto, ON, Canada.
authors.forename: Eliana
authors.initials: E
authors.lastname: Vonapartis
authors.affiliation: College of Horticulture, Sichuan Agricultural University Ya'an, China.
authors.forename: Xian
authors.initials: X
authors.lastname: Luo
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University Beijing, China.
authors.forename: Benhe
authors.initials: B
authors.lastname: Gong
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University Beijing, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Liu
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University Beijing, China.
authors.forename: Chenyu
authors.initials: C
authors.lastname: Wu
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University Beijing, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Liu
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University Beijing, China.
authors.forename: Fengqin
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University Beijing, China.
authors.forename: Junna
authors.initials: J
authors.lastname: He
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture and Landscape Architecture, China Agricultural University Beijing, China.
authors.forename: Mingfang
authors.initials: M
authors.lastname: Yi
keywords: ABA; GhABI5; Gladiolus hybridus; corm; dormancy