title: A bHLH transcription factor, DvIVS, is involved in regulation of anthocyanin synthesis in dahlia (Dahlia variabilis).
abstract: Dahlias (Dahlia variabilis) exhibit a wide range of flower colours because of accumulation of anthocyanin and other flavonoids in their ray florets. Two lateral mutants were used that spontaneously occurred in 'Michael J' (MJW) which has yellow ray florets with orange variegation. MJOr, a bud mutant producing completely orange ray florets, accumulates anthocyanins, flavones, and butein, and MJY, another mutant producing completely yellow ray florets, accumulates flavones and butein. Reverse transcription-PCR analysis showed that expression of chalcone synthase 1 (DvCHS1), flavanone 3-hydroxylase (DvF3H), dihydroflavonol 4-reductase (DvDFR), anthocyanidin synthase (DvANS), and DvIVS encoding a basic helix-loop-helix transcription factor were suppressed, whereas that of chalcone isomerase (DvCHI) and DvCHS2, another CHS with 69% nucleotide identity with DvCHS1, was not suppressed in the yellow ray florets of MJY. A 5.4 kb CACTA superfamily transposable element, transposable element of Dahlia variabilis 1 (Tdv1), was found in the fourth intron of the DvIVS gene of MJW and MJY, and footprints of Tdv1 were detected in the variegated flowers of MJW. It is shown that only one type of DvIVS gene was expressed in MJOr, whereas these plants are likely to have three types of the DvIVS gene. On the basis of these results, the mechanism regulating the formation of orange and yellow ray florets in dahlia is discussed.
authors.affiliation: Graduate School of Agriculture, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan.
authors.forename: Sho
authors.initials: S
authors.lastname: Ohno
authors.forename: Munetaka
authors.initials: M
authors.lastname: Hosokawa
authors.forename: Atsushi
authors.initials: A
authors.lastname: Hoshino
authors.forename: Yoshikuni
authors.initials: Y
authors.lastname: Kitamura
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Morita
authors.forename: Kyeung-Ii
authors.initials: KI
authors.lastname: Park
authors.forename: Akiko
authors.initials: A
authors.lastname: Nakashima
authors.forename: Ayumi
authors.initials: A
authors.lastname: Deguchi
authors.forename: Fumi
authors.initials: F
authors.lastname: Tatsuzawa
authors.forename: Motoaki
authors.initials: M
authors.lastname: Doi
authors.forename: Shigeru
authors.initials: S
authors.lastname: Iida
authors.forename: Susumu
authors.initials: S
authors.lastname: Yazawa
mesh_terms: D000595:Amino Acid Sequence; D000872:Anthocyanins / Q000096:biosynthesis*; D051792:Basic Helix-Loop-Helix Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D053898:Biosynthetic Pathways; D031944:Dahlia / Q000737:chemistry / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D035264:Flowers / Q000737:chemistry / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment
chemical_list: D000872:Anthocyanins; D051792:Basic Helix-Loop-Helix Proteins; D010940:Plant Proteins