title: An Ethylene-Induced Regulatory Module Delays Flower Senescence by Regulating Cytokinin Content.
abstract: In many plant species, including rose (Rosa hybrida), flower senescence is promoted by the gaseous hormone ethylene and inhibited by the cytokinin (CTK) class of hormones. However, the molecular mechanisms underlying these antagonistic effects are not well understood. In this study, we characterized the association between a pathogenesis-related PR-10 family gene from rose (RhPR10.1) and the hormonal regulation of flower senescence. Quantitative reverse transcription PCR analysis showed that RhPR10.1 was expressed at high levels during senescence in different floral organs, including petal, sepal, receptacle, stamen, and pistil, and that expression was induced by ethylene treatment. Silencing of RhPR10.1 expression in rose plants by virus-induced gene silencing accelerated flower senescence, which was accompanied by a higher ion leakage rate in the petals, as well as increased expression of the senescence marker gene RhSAG12 CTK content and the expression of three CTK signaling pathway genes were reduced in RhPR10.1-silenced plants, and the accelerated rate of petal senescence that was apparent in the RhPR10.1-silenced plants was restored to normal levels by CTK treatment. Finally, RhHB6, a homeodomain-Leu zipper I transcription factor, was observed to bind to the RhPR10.1 promoter, and silencing of its expression also promoted flower senescence. Our results reveal an ethylene-induced RhHB6-RhPR10.1 regulatory module that functions as a brake of ethylene-promoted senescence through increasing the CTK content.
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, China Agricultural University, Beijing 100193, PR China (L.W., N.M., Y.J., Y.Z., M.F., J.G.).|Crops Pathology and Genetic Research Unit, United States Department of Agriculture Agricultural Research Service, Davis, California 95616 (C.-Z.J.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (C.-Z.J.).
authors.forename: Lin
authors.initials: L
authors.lastname: Wu
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, China Agricultural University, Beijing 100193, PR China (L.W., N.M., Y.J., Y.Z., M.F., J.G.).|Crops Pathology and Genetic Research Unit, United States Department of Agriculture Agricultural Research Service, Davis, California 95616 (C.-Z.J.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (C.-Z.J.).
authors.forename: Nan
authors.initials: N
authors.lastname: Ma
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, China Agricultural University, Beijing 100193, PR China (L.W., N.M., Y.J., Y.Z., M.F., J.G.).|Crops Pathology and Genetic Research Unit, United States Department of Agriculture Agricultural Research Service, Davis, California 95616 (C.-Z.J.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (C.-Z.J.).
authors.forename: Yangchao
authors.identifier: 0000-0002-6288-7917
authors.initials: Y
authors.lastname: Jia
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, China Agricultural University, Beijing 100193, PR China (L.W., N.M., Y.J., Y.Z., M.F., J.G.).|Crops Pathology and Genetic Research Unit, United States Department of Agriculture Agricultural Research Service, Davis, California 95616 (C.-Z.J.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (C.-Z.J.).
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, China Agricultural University, Beijing 100193, PR China (L.W., N.M., Y.J., Y.Z., M.F., J.G.).|Crops Pathology and Genetic Research Unit, United States Department of Agriculture Agricultural Research Service, Davis, California 95616 (C.-Z.J.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (C.-Z.J.).
authors.forename: Ming
authors.initials: M
authors.lastname: Feng
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, China Agricultural University, Beijing 100193, PR China (L.W., N.M., Y.J., Y.Z., M.F., J.G.).|Crops Pathology and Genetic Research Unit, United States Department of Agriculture Agricultural Research Service, Davis, California 95616 (C.-Z.J.); and.|Department of Plant Sciences, University of California, Davis, California 95616 (C.-Z.J.).
authors.forename: Cai-Zhong
authors.identifier: 0000-0002-5972-7963
authors.initials: CZ
authors.lastname: Jiang
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, China Agricultural University, Beijing 100193, PR China (L.W., N.M., Y.J., Y.Z., M.F., J.G.); mac@cau.edu.cn gaojp@cau.edu.cn.|Crops Pathology and Genetic Research Unit, United States Department of Agriculture Agricultural Research Service, Davis, California 95616 (C.-Z.J.); and mac@cau.edu.cn gaojp@cau.edu.cn.|Department of Plant Sciences, University of California, Davis, California 95616 (C.-Z.J.) mac@cau.edu.cn gaojp@cau.edu.cn.
authors.forename: Chao
authors.identifier: 0000-0002-3866-0894
authors.initials: C
authors.lastname: Ma
authors.affiliation: Beijing Key Laboratory of Development and Quality Control of Ornamental Crops, Department of Ornamental Horticulture, China Agricultural University, Beijing 100193, PR China (L.W., N.M., Y.J., Y.Z., M.F., J.G.); mac@cau.edu.cn gaojp@cau.edu.cn.|Crops Pathology and Genetic Research Unit, United States Department of Agriculture Agricultural Research Service, Davis, California 95616 (C.-Z.J.); and mac@cau.edu.cn gaojp@cau.edu.cn.|Department of Plant Sciences, University of California, Davis, California 95616 (C.-Z.J.) mac@cau.edu.cn gaojp@cau.edu.cn.
authors.forename: Junping
authors.identifier: 0000-0002-9285-2539
authors.initials: J
authors.lastname: Gao
mesh_terms: D003583:Cytokinins / Q000378:metabolism*; D005030:Ethylenes / Q000378:metabolism / Q000494:pharmacology*; D035264:Flowers / Q000187:drug effects / Q000502:physiology*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D020868:Gene Silencing; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D027826:Rosa / Q000187:drug effects / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D003583:Cytokinins; D005030:Ethylenes; D010940:Plant Proteins; D014157:Transcription Factors; C036216:ethylene