The AtMYB12 activation domain maps to a short C-terminal region of the transcription factor.
The Arabidopsis thaliana R2R3-MYB transcription factor MYB12 is a light-inducible, flavonol-specific activator of flavonoid biosynthesis. The transactivation activity of the AtMYB12 protein was analyzed using a C-terminal deletion series in a transient A. thaliana protoplast assay with the goal of mapping the activation domain (AD). Although the deletion of the last 46 C-terminal amino acids did not affect the activation capacity, the deletion of the last 98 amino acids almost totally abolished transactivation of two different target promoters. A domain swap experiment using the yeast GAL4 DNA-binding domain revealed that the region from positions 282 to 328 of AtMYB12 was sufficient for transactivation. In contrast to the R2R3-MYB ADs known thus far, that of AtMYB12 is not located at the rearmost C-terminal end of the protein. The AtMYB12 AD is conserved in other experimentally proven R2R3-MYB flavonol regulators from different species.
['Stracke|Ralf|R|', 'Turgut-Kara|Neslihan|N|', 'Weisshaar|Bernd|B|']
D000595:Amino Acid Sequence D017360:Arabidopsis D029681:Arabidopsis Proteins D001665:Binding Sites D005419:Flavonoids D018506:Gene Expression Regulation, Plant D005966:Glucuronidase D009154:Mutation D030821:Plants, Genetically Modified D011401:Promoter Regions, Genetic D011523:Protoplasts D036226:Seedlings D017384:Sequence Deletion D017386:Sequence Homology, Amino Acid D014157:Transcription Factors D015533:Transcriptional Activation
activation domain transcription factor MYB12 flavonol regulator production of flavonol glycosides