title: GA-DELLA pathway is involved in regulation of nitrogen deficiency-induced anthocyanin accumulation.
abstract: DELLA proteins positively regulate nitrogen deficiency-induced anthocyanin accumulation through directly interaction with PAP1 to enhance its transcriptional activity on anthocyanin biosynthetic gene expressions. Plants can survive a limiting nitrogen supply by undergoing adaptive responses, including induction of anthocyanin production. However, the detailed mechanism is still unclear. In this study, we found that this process was impaired and enhanced, respectively, by exogenous GA3(an active form of GAs) and paclobutrazol (PAC, a specific GA biosynthesis inhibitor) in Arabidopsis seedlings. Consistently, the nitrogen deficiency-induced transcript levels of several key genes involved in anthocyanin biosynthesis, including F3'H, DFR, LDOX, and UF3GT, were decreased and enhanced by exogenous GA3and PAC, respectively. Moreover, the nitrogen deficiency-induced anthocyanin accumulation and biosynthesis gene expressions were impaired in the loss-of-function mutant gai-t6/rga-t2/rgl1-1/rgl2-1/rgl3-1 (della) but enhanced in the GA-insensitive mutant gai, suggesting that DELLA proteins, known as repressors of GA signaling, are necessary for fully induction of nitrogen deficiency-driven anthocyanin biosynthesis. Using yeast two-hybrid (Y2H) assay, pull-down assay, and luciferase complementation assay, it was found that RGA, a DELLA of Arabidopsis, could strongly interact with PAP1, a known regulatory transcription factor positively involved in anthocyanin biosynthesis. Furthermore, transient expression assays indicated that RGA and GAI could enhance the transcriptional activities of PAP1 on its downstream genes, including F3'H and DFR. Taken together, this study suggests that DELLAs are necessary regulators for nitrogen deficiency-induced anthocyanin accumulation through interaction with PAP1 and enhancement of PAP1's transcriptional activity on its target genes. GA-DELLA-involved anthocyanin accumulation is important for plant adaptation to nitrogen deficiency.
authors.affiliation: Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.|Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.|Key Laboratory of Cell Activities and Stress Adaptations, Ministry of Education, School of Life Sciences, Lanzhou University, Lanzhou, 730000, People's Republic of China.
authors.forename: Yongqiang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.|Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.
authors.forename: Zhongjuan
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.|Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Liu
authors.affiliation: Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.|Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Lin
authors.affiliation: State Key Laboratory of Grassland Agro-Ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, 730000, People's Republic of China.
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Wang
authors.affiliation: Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China. lwx@fafu.edu.cn.|Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China. lwx@fafu.edu.cn.
authors.forename: Wenxiong
authors.initials: W
authors.lastname: Lin
authors.affiliation: Fujian Provincial Key Laboratory of Agroecological Processing and Safety Monitoring, School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China. wfxu@fafu.edu.cn.|Key Laboratory of Ministry of Education for Genetics, Breeding and Multiple Utilization of Crops, Fujian Agriculture and Forestry University, Fuzhou, 350002, People's Republic of China. wfxu@fafu.edu.cn.
authors.forename: Weifeng
authors.initials: W
authors.lastname: Xu
mesh_terms: D000872:Anthocyanins / Q000235:genetics / Q000378:metabolism*; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000235:genetics*; D005875:Gibberellins / Q000494:pharmacology; D009584:Nitrogen / Q000172:deficiency* / Q000378:metabolism; D000073718:Pancreatitis-Associated Proteins; D030821:Plants, Genetically Modified / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D000872:Anthocyanins; D029681:Arabidopsis Proteins; D005875:Gibberellins; D009584:Nitrogen; D000073718:Pancreatitis-Associated Proteins; D014157:Transcription Factors; C109555:GAI protein, Arabidopsis; C502612:AT1G56650 protein, Arabidopsis; C000612141:REG3A protein, human
keywords: Anthocyanin; Arabidopsis; DELLA; Gibberellin; Nitrogen deficiency; Production of anthocyanin pigment 1