title: Cloning and characterization of a flavonol synthase gene from Scutellaria baicalensis.
abstract: Flavonols are the most abundant of all the flavonoids and play pivotal roles in a variety of plants. We isolated a cDNA clone encoding flavonol synthase from Scutellaria baicalensis (SbFLS). The SbFLS cDNA is 1011 bp long, encodes 336 amino acid residues, and belongs to a family of 2-oxoglutarate-dependent dioxygenases. The overall structure of SbFLS is very similar to that of Arabidopsis thaliana anthocyanidin synthase (AtANS), with a β jelly-roll fold surrounded by tens of short and long α-helices. SbFLS was constitutively expressed in the roots, stems, leaves, and flowers, with particularly high expression in the roots and flowers. SbFLS transcript levels in the roots were 376-, 70-, and 2.5-fold higher than in the leaves, stems, and flowers. The myricetin content was significantly higher than that of kaempferol and quercetin. Therefore, we suggest that SbFLS mediates flavonol formation in the different organs of S. baicalensis. Our study may contribute to the knowledge of the role of FLS in S. baicalensis.
authors.affiliation: Department of Crop Science, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 305-764, Republic of Korea.
authors.forename: Yeon Bok
authors.initials: YB
authors.lastname: Kim
authors.affiliation: Department of Biochemistry and Molecular Biology, Baylor College of Medicine One Baylor Plaza, Houston, TX 77030, USA.
authors.forename: KwangSoo
authors.initials: K
authors.lastname: Kim
authors.affiliation: Department of Crop Science, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 305-764, Republic of Korea.
authors.forename: Yeji
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Crop Science, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 305-764, Republic of Korea.
authors.forename: Pham Anh
authors.initials: PA
authors.lastname: Tuan
authors.affiliation: Department of Well-Being Resources, Sunchon National University, 413 Jungangno, Suncheon, Jeollanam-do 540-742, Republic of Korea.
authors.forename: Haeng Hoon
authors.initials: HH
authors.lastname: Kim
authors.affiliation: Department of Crop Science, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 305-764, Republic of Korea.
authors.forename: Jin Woong
authors.initials: JW
authors.lastname: Cho
authors.affiliation: Department of Crop Science, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 305-764, Republic of Korea.
authors.forename: Sang Un
authors.initials: SU
authors.lastname: Park
mesh_terms: D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D044948:Flavonols / Q000378:metabolism; D008958:Models, Molecular; D009928:Organ Specificity / Q000235:genetics; D010088:Oxidoreductases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011487:Protein Conformation; D031364:Scutellaria baicalensis / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D017422:Sequence Analysis, DNA; D014158:Transcription, Genetic
chemical_list: D018076:DNA, Complementary; D044948:Flavonols; D010940:Plant Proteins; D010088:Oxidoreductases; C085313:flavonol synthase