Brassinosteroid Biosynthetic Gene CmDWF4 Regulates Bud Outgrowth in Chrysanthemum morifolium  

作　　者：Xianrong Fu Aiping Song Bo Peng Song Li Weixin Liu Lingling Zhang Jiafu Jiang Sumei Chen Fadi Chen 

机构地区：[1]State Key Laboratory of Crop Genetics and Germplasm Enhancement and Utilization,Key Laboratory of Landscaping,Key Laboratory of Flower Biology and Germplasm Innovation(South),Ministry of Agriculture and Rural Affairs,Key Laboratory of Biology of Ornamental Plants in East China,National Forestry and Grassland Administration,College of Horticulture,Nanjing Agricultural University,Nanjing,210095,China

出　　处：《Phyton-International Journal of Experimental Botany》2023年第6期1681-1694,共14页国际实验植物学杂志（英文）

基　　金：This research was funded by the National Natural Science Foundation of China(31872149,32172609);China Agriculture Research System(CARS-23-A18),the“JBGS”Project of Seed Industry Revitalization in Jiangsu Province(JBGS[2021]020);the earmarked fund for Jiangsu Agricultural Industry Technology System,and a project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.

摘　　要：Brassinosteroids(BRs),a class of steroid phytohormones,play a critical role in plant growth and development.The DWF4 gene encodes a cytochrome P450 enzyme(CYP90B1),which is considered a rate-limiting enzyme in BR biosynthesis.Here,we identified a homologous gene of DWF4 in chrysanthemum,CmDWF4.This gene was predicted to encode 491 amino acid residues with a molecular weight of 56.2 kDa and an isoelectric point(pI)of 9.10.Overexpression of CmDWF4 in chrysanthemum was found to significantly increase growth rate,number,and length of lateral buds.Transcriptome analysis showed that multiple xyloglucan endotransglycosylase/hydrolase(XTH)family encoding genes associated with cell wall modification were up-regulated in CmDWF4-overexpressing lines.qRT-PCR assay confirmed the up-regulation of CmXTH6,CmXTH23,and CmXTH28 in CmDWF4-overexpression line.Overall,this work establishes a mechanism by which BR biosynthetic gene CmDWF4 promotes lateral bud outgrowth in chrysanthemum,possibly through regulating cell elongation and expansion.

关 键 词：BR axillary bud shoot branching XTHs cell elongation 

分 类 号：S682.11[农业科学—观赏园艺]