Affiliation:
1. Max-Planck-Institute for Plant Breeding Research, D–50829 Cologne, Germany
Abstract
Abstract
Comprehensive functional data on plant R2R3-MYB transcription factors is still scarce compared to the manifold of their occurrence. Here, we identified the Arabidopsis (Arabidopsis thaliana) R2R3-MYB transcription factor MYB12 as a flavonol-specific activator of flavonoid biosynthesis. Transient expression in Arabidopsis protoplasts revealed a high degree of functional similarity between MYB12 and the structurally closely related factor P from maize (Zea mays). Both displayed similar target gene specificity, and both activated target gene promoters only in the presence of a functional MYB recognition element. The genes encoding the flavonoid biosynthesis enzymes chalcone synthase, chalcone flavanone isomerase, flavanone 3-hydroxylase, and flavonol synthase were identified as target genes. Hence, our observations further add to the general notion of a close relationship between structure and function of R2R3-MYB factors. High-performance liquid chromatography analyses of myb12 mutant plants and MYB12 overexpression plants demonstrate a tight linkage between the expression level of functional MYB12 and the flavonol content of young seedlings. Quantitative real time reverse transcription-PCR using these mutant plants showed MYB12 to be a transcriptional regulator of CHALCONE SYNTHASE and FLAVONOL SYNTHASE in planta, the gene products of which are indispensable for the biosynthesis of flavonols.
Publisher
Oxford University Press (OUP)
Subject
Plant Science,Genetics,Physiology
Reference66 articles.
1. Andersson KB, Berge T, Matre V, Gabrielsen OS (1999) Sequence selectivity of c-Myb in vivo. Resolution of a DNA target specificity paradox. J Biol Chem274:21986–21994
2. Armstrong GA, Weisshaar B, Hahlbrock K (1992) Homodimeric and heterodimeric leucine zipper proteins and nuclear factors from parsley recognize diverse promoter elements with ACGT cores. Plant Cell4:525–537
3. Baudry A, Heim MA, Dubreucq B, Caboche M, Weisshaar B, Lepiniec L (2004) TT2, TT8, and TTG1 synergistically specify the expression of BANYULS and proanthocyanidin biosynthesis in Arabidopsis thaliana. Plant J39:366–380
4. Bechtold N, Ellis J, Pelletier G (1993) In planta Agrobacterium mediated gene transfer by infiltration of adult Arabidopsis thaliana plants. C R Acad Sci Paris Life Sci316:1194–1199
5. Becker D, Kemper E, Schell J, Masterson R (1992) New plant binary vectors with selectable markers located proximal to the left T-DNA border. Plant Mol Biol20:1195–1197
Cited by
674 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献