title: Investigation of cytokinin-deficient phenotypes in Arabidopsis by ectopic expression of orchid DSCKX1.
abstract: The plant hormone cytokinin plays a major role in regulating plant growth and development. Here we generated cytokinin-reduction Arabidopsis plants by overexpressing a heterologous cytokinin oxidase gene DSCKX1 from Dendrobium orchid. These transgenic plants exhibited reduced biomass, rapid root growth, decreased ability to form roots in vitro, and reduced response to cytokinin in growing calli and roots. Furthermore, the expression of KNAT1, STM, and CycD3 genes was significantly reduced in the transgenic plants, suggesting that cytokinin may function to control the cell cycles and shoot/root development via regulation of these genes.
authors.affiliation: Department of Biological Sciences, Faculty of Science, National University of Singapore, 10 Science Drive 4, 117543, Singapore. sy226@cornell.edu
authors.forename: Shuhua
authors.initials: S
authors.lastname: Yang
authors.forename: Hao
authors.initials: H
authors.lastname: Yu
authors.forename: Yifeng
authors.initials: Y
authors.lastname: Xu
authors.forename: Chong Jin
authors.initials: CJ
authors.lastname: Goh
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000096:biosynthesis / Q000235:genetics; D016213:Cyclins / Q000096:biosynthesis; D003583:Cytokinins / Q000235:genetics / Q000494:pharmacology / Q000502:physiology*; D031667:Dendrobium / Q000201:enzymology* / Q000235:genetics*; D018506:Gene Expression Regulation, Plant / Q000235:genetics; D017343:Genes, Plant; D018398:Homeodomain Proteins / Q000096:biosynthesis / Q000235:genetics; D007541:Isopentenyladenosine / Q000032:analysis; D010088:Oxidoreductases / Q000096:biosynthesis* / Q000235:genetics*; D010641:Phenotype; D018514:Plant Structures / Q000235:genetics / Q000254:growth & development; D030821:Plants, Genetically Modified; D018749:RNA, Plant / Q000302:isolation & purification
chemical_list: D029681:Arabidopsis Proteins; D016213:Cyclins; D003583:Cytokinins; D018398:Homeodomain Proteins; C092212:KNAT1 protein, Arabidopsis; D018749:RNA, Plant; C097496:STM protein, Arabidopsis; D007541:Isopentenyladenosine; D010088:Oxidoreductases; C019984:cytokinin oxidase