title: MYBD employed by HY5 increases anthocyanin accumulation via repression of MYBL2 in Arabidopsis.
abstract: Photomorphogenesis is an essential program in plant development. This process is effected by the balanced cooperation of many factors under light and dark conditions. In a previous study, we showed that MYB hypocotyl elongation-related (MYBH) is involved in cell elongation. To expand our understanding of MYBH function, we performed a yeast two-hybrid assay and identified an MYB-like Domain transcription factor (MYBD). In this study, we investigated the function of MYBD, which is an MYBH homolog involved in anthocyanin accumulation. MYBD expression increased in response to light or cytokinin, and MYBD enhanced anthocyanin biosynthesis via repression of MYBL2, which encodes a transcription factor that has a negative effect on this process. In addition, MYBD binding in vivo to the MYBL2 promoter and the lower level of histone H3K9 acetylation at the upstream region of MYBL2 in MYBD over-expressing plants in comparison with wild-type plants imply that MYBD represses MYBL2 expression via an epigenetic mechanism. HY5 directly binds to the MYBD promoter, which indicates that MYBD acts on HY5-downstream in light- or cytokinin-triggered signaling pathways, leading to anthocyanin accumulation. Our results suggest that, although MYBD and MYBH are homologs, they act in opposite ways during plant photomorphogenesis, and these functions should be examined in further studies.
authors.affiliation: Department of Biosystems and Biotechnology, College of Life Sciences and Biotechnology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul, 136-713, Korea.|Institute of Life Science and Natural Resources, Korea University, Seoul, 136-713, Korea.
authors.forename: Nguyen Hoai
authors.initials: NH
authors.lastname: Nguyen
authors.affiliation: Department of Biosystems and Biotechnology, College of Life Sciences and Biotechnology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul, 136-713, Korea.|Institute of Life Science and Natural Resources, Korea University, Seoul, 136-713, Korea.
authors.forename: Chan Young
authors.initials: CY
authors.lastname: Jeong
authors.affiliation: Department of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul, 136-713, Korea.
authors.forename: Geun-Ho
authors.initials: GH
authors.lastname: Kang
authors.affiliation: Department of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul, 136-713, Korea.
authors.forename: Sang-Dong
authors.initials: SD
authors.lastname: Yoo
authors.affiliation: Department of Molecular Biotechnology, College of Agriculture and Life Sciences, Bioenergy Research Center, Chonnam National University, Gwangju, Korea.
authors.forename: Suk-Whan
authors.initials: SW
authors.lastname: Hong
authors.affiliation: Department of Biosystems and Biotechnology, College of Life Sciences and Biotechnology, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul, 136-713, Korea.|Institute of Life Science and Natural Resources, Korea University, Seoul, 136-713, Korea.
authors.forename: Hojoung
authors.initials: H
authors.lastname: Lee
mesh_terms: D000872:Anthocyanins / Q000378:metabolism*; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics / Q000378:metabolism*; D003583:Cytokinins; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D008027:Light; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D000872:Anthocyanins; D029681:Arabidopsis Proteins; C103684:AtmybL2 protein, Arabidopsis; D050976:Basic-Leucine Zipper Transcription Factors; D003583:Cytokinins; D004268:DNA-Binding Proteins; C109254:HY5 protein, Arabidopsis; C000611665:MYBD protein, Arabidopsis; D009687:Nuclear Proteins; D012097:Repressor Proteins; D014157:Transcription Factors
keywords: Arabidopsis thaliana; MYBD (AT1G70000); MYBL2 (AT1G71030); anthocyanin; cytokinin; histone acetylation; photomorphogenesis