Date of Award
5-3-2013
Document Type
Thesis
Degree Name
Biology, MS
First Advisor
Fabricio Medina-Bolivar
Committee Members
Argelia Lorence; Giuliana Medrano; Nirmal Joshee
Abstract
American skullcap (Scutellaria lateriflora), a perennial herb native to America, is rich in specialized metabolites that have shown various biological activities. In particular, the flavonoids wogonin, baicalein and baicalin have proven anticancer properties in vitro. However, the regulatory mechanisms and biosynthetic steps leading to these specialized metabolites have not been elucidated. To address this issue, hairy root cultures of S. lateriflora expressing the flavonoid-specific transcription factor AtMYB12 from Arabidopsis thaliana were developed using Agrobacterium rhizogenes ATCC 15834 containing a binary vector harboring the AtMYB12 cDNA under the control of the SuperP:TEV expression system. In this study, three AtMYB12 transgenic hairy root lines of S. lateriflora were successfully established. High performance liquid chromatography (HPLC) and Liquid chromatography-tandem mass spectrometry (LC-MS) analysis confirmed the presence of the phenylpropanoid compound verbascoside and the flavonoids bacailein, baicalin, wogonin and wogonoside in the hairy roots of S. lateriflora. Semi-quantitative RT-PCR analysis showed an increase the expression of PAL and CHI in the transgenic AtMYB12-hairy root line when compared to a wild-type line. Interestingly, the accumulation of wogonin was increased in the AtMYB12 transgenic hairy root lines. Moreover, preliminary characterization of two unknown compounds, a flavone and a glucuronide derived from this flavone, were characterized in the S. lateriflora hairy roots by HPLC and LC-MS analysis. In summary, the AtMYB12 hairy root culture can be used to study the biosynthesis of phenolics and particularly flavonoids in this species under the regulation of AtMYB12 transcription factor.
Rights Management
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Yang, Tianhong, "Metabolic engineering of flavonoid biosynthesis in Scutellaria lateriflora hairy roots by ectopic expression of the AtMYB12 transcription factor" (2013). Student Theses and Dissertations. 795.
https://arch.astate.edu/all-etd/795
