title: Melatonin mediates the stabilization of DELLA proteins to repress the floral transition in Arabidopsis.
abstract: Precise floral transition from vegetative growth phase to reproductive growth phase is very important in plant life cycle. In flowering genetic pathways, DELLA proteins are master transcriptional regulators of gibberelic acid (GA) pathway, and FLOWERING LOCUS C (FLC) is a core repressor of vernalization pathway as well as downstream of DELLAs. As a crucial messenger in plants, the possible involvement of melatonin (N-acetyl-5-methoxytryptamine) in flowering and underlying molecular mechanism are unknown in Arabidopsis. In this study, we found that exogenous melatonin treatment delayed floral transition in Arabidopsis. Exogenous melatonin treatment conferred protein stabilizations of DELLAs [REPRESSOR of ga1-3 (RGA) and RGA-LIKE3 (RGL3)], without regulating the transcripts of DELLAs and endogenous GA level. Notably, exogenous melatonin delayed plant flowering and DELLA-activated transcripts of FLC were alleviated in della mutants, and those were exacerbated in DELLA overexpressing plants. Taken together, this study provides direct link between melatonin and floral transition, and indicates the novel involvement of DELLAs-activated FLC in melatonin-mediated flowering in Arabidopsis.
authors.affiliation: Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Agriculture, Hainan University, Haikou, China.
authors.forename: Haitao
authors.initials: H
authors.lastname: Shi
authors.affiliation: Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Agriculture, Hainan University, Haikou, China.
authors.forename: Yunxie
authors.initials: Y
authors.lastname: Wei
authors.affiliation: Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Agriculture, Hainan University, Haikou, China.
authors.forename: Qiannan
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Department of Cellular and Structural Biology, The University of Texas Health Science Center, San Antonio, TX, USA.
authors.forename: Russel J
authors.initials: RJ
authors.lastname: Reiter
authors.affiliation: Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources, College of Agriculture, Hainan University, Haikou, China.
authors.forename: Chaozu
authors.initials: C
authors.lastname: He
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000378:metabolism*; D005875:Gibberellins / Q000235:genetics / Q000378:metabolism; D026161:MADS Domain Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D055550:Protein Stability
chemical_list: D029681:Arabidopsis Proteins; C418902:At5g10140 protein, Arabidopsis; C109555:GAI protein, Arabidopsis; D005875:Gibberellins; D026161:MADS Domain Proteins; C007842:gibberellic acid
keywords: Arabidopsis; DELLA; FLC; Melatonin; floral transition; gibberelic acid