Search
 
  Home
  About us
  News
  Our Teams
  Resources
  Education & Training
  Join us
  Contact
  Link
 
 
 
News

Scientists have elucidated the whole biosynthesis pathway of baicalein in Scutellariabaicalensis

 

ScutellariabaicalensisGeorgi, or Huangqin, is a species of flowering plant in the Lamiaceae family. The medicinal plant has been widely used in China for thousands of years. Flavones likebaicaleinand wogonin are the major bioactive compounds extracted from the root of S. baicalensis. These flavones have been reported to have various pharmacological functions, such as hepatoprotection, antibacterial and antiviral, antioxidant, anticonvulsant and neuroprotective effects. Baicaleinand wogonin could induce apoptosis specifically in cancer cells while having no effects on normal cells.

 

Recently, scientists from Chenshan Botanical Garden/Shanghai Chenshan Plant Science Research Center of Chinese Academy of Sciences, Shanghai Institute of Plant Physiology and Ecology, and John Innes Centre of UK, leaded by Prof. Cathie Martin and Dr. Qing Zhao have elucidated the whole biosynthesis pathway of baicalein in Scutellariabaicalensis. Cathie’s group reported the identification of two flavone hydroxylases from S. baicalensis,they all belong to plant Cyt p450 enzymes. SbCYP82D1.1 encodes a flavone 6-hydroxylase with broad specificity to flavones, and is responsible for the biosynthesis of baicalein and scutellarein. SbCYP82D1.1 can convert flavones without 7-O-methyl groups such as chrysin and agipigenin. When the transcripts of SbCYP82D1.1 were down-regulated using RNAi, baicalein content was reduced significantly while chrysin glycosides accumulated in the RNAi hairy roots. SbCYP82D2 likely evolved from SbCYP82D1.1 through gene duplication. Interestingly, the protein encoded by SbCYP82D2 is a flavone 8-hydroxylase, and accepts only chrysin as substrate to produce norwogonin. This work extends our previous work to elucidate the entire biosynthetic pathway for baicalein.

 

The paper entitled “Two CYP82D enzymes function as flavone hydroxylases in the biosynthesis of root-specific 4′-deoxyflavones in Scutellariabaicelensis” has been published online in Molecular Plant on 22th August, 2017. Prof. Cathie Martin is the corresponding author. Dr. Qing Zhao and Miss Meng-Ying Cui are the co-first authours. This project was collaborated with Prof. Xiao-Ya Chen from SIPPE, Prof. Yonghong Hu from Chenshan Botanical Garden and Jing-Ke Weng from MIT. The study was supported by Chenshan Special Fund for Shanghai Landscaping Administration Bureau Program and Natural Science Foundation of China.

 

Article website: http://www.cell.com/molecular-plant/abstract/S1674-2052(17)30239-3

 

Author contact:
Dr. Cathie Martin, Professor
Chenshan Botanical Garden or John Innes Centre

Tel: +44 (0) 1603 450275
E-mail:
cathie.martin@jic.ac.uk

 
 
Shanghai Chenshan Plant Science Research Center, Chinese Academy of Sciences All Rights Reserved
Address: Chen Hua Road, Songjiang District, Shanghai Post Code 201602
Tel:3888 -21-37792288 Fax:86 -21-67657811 E-mail: webmaster@scpsrc.ac.cn