title: Isolation and functional analysis of a homolog of flavonoid 3',5'-hydroxylase gene from Pericallis × hybrida.
abstract: As the key enzyme in the biosynthesis of blue flower color pigments, flavonoid 3',5'-hydroxylase (F3'5'H) can catalyze the conversion of its major substrates, 2-S naringenin and dihydrokaempferol, into 3',4',5'-hydroxylated pentahydroxyflavanone and dihydromyricetin, respectively. Unlike other F3'5'Hs belonging to the CYP75A subfamily, Asteraceae-specific F3'5'Hs belong to the CYP75B subfamily. Furthermore, cineraria F3'5'H expressed in yeast exhibited not only F3'H (flavonoid 3'-hydroxylase) activity but also F3'5'H activity in vitro. In this study, Southern blotting showed that there was only one copy of a homolog of the F3'5'H gene PCFH in the Pericallis × hybrida genome. This gene could be detected by Northern blot in the primary developmental stages of ligulate florets of the purple- and blue-flowered cultivars, and its transcripts also accumulated in the leaves. Heterologous expression of PCFH could produce new delphinidin derivatives in the corollas of transgenic tobacco plants, increased the content of cyanidin derivatives and lead to the blue- and red-shifting of flower color in T₀ generation plants. These results indicate that cineraria F3'5'H exhibited both F3'5'H- and F3'H-activity in vivo. The types and contents of anthocyanins and flower color phenotypes of the T₁ generation were similar to those of T₀ generation plants. PCFH exhibited stable inheritance and normal functions between generations. This study supplies new evidence to understand Asteraceae-specific F3'5'Hs and provides important references for the further study of molecular breeding of blue-flowered chrysanthemums using the PCFH gene.
authors: College of Landscape Architecture, Beijing Forestry University, Beijing, 100083, China; Forestry and Fruit Research Institute, Shanghai Academy of Agricultural Sciences, Shanghai, 201403, China.
authors: Yi
authors: Y
authors: Sun
authors: He
authors: H
authors: Huang
authors: Li
authors: L
authors: Meng
authors: Ke
authors: K
authors: Hu
authors: Si-Lan
authors: SL
authors: Dai
mesh_terms: D000872:Anthocyanins / Q000378:metabolism; D019659:Asteraceae / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D015152:Blotting, Northern; D003116:Color; D003577:Cytochrome P-450 Enzyme System / Q000235:genetics* / Q000378:metabolism; D035264:Flowers / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D010858:Pigmentation / Q000235:genetics; D018515:Plant Leaves / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D018517:Plant Roots / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D018547:Plant Stems / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D030821:Plants, Genetically Modified; D014026:Nicotiana / Q000235:genetics / Q000254:growth & development / Q000378:metabolism
chemical_list: D000872:Anthocyanins; D010940:Plant Proteins; D003577:Cytochrome P-450 Enzyme System; C084258:flavonoid 3',5'-hydroxylase