Liu Tao, Mu Lan, Liang Yan-Li, Wang Jian-Jun, Yang Sheng-Chao
Yunnan Research Center on Good Agricultural Practice for Dominant Chinese Medicinal Materials, Yunnan Agricultural University, Kunming 650201, China.
Zhongguo Zhong Yao Za Zhi. 2013 Jul;38(14):2241-4.
Scutellarin from Erigeron breviscapus is a flavonoid with remarkable pharmacological activity, whose route of biosynthesis is still fully clear. Chalcone synthase (CHS) is the key enzyme regulating flavonoids biosynthesis, and the aim of this study is to explain the relationship between patterns of the gene expression and scutellarin content through studying CHS gene expression patterns combined with scutellarin content in various parts of E. breviscapus.
Through RT-PCR and RACE, the full length of CHS was cloned and analyzed by fluorescent quantitative PCR. The scutellarin content in tissues was analyzed by HPLC.
The full-length gene sequence was 1 270 bp, encoding 405 amino acids. Software analysis found that the DNA sequence was 80% similarity with Compositae plant homeo-box gene. Fluorescence quantitative analysis showed that CHS had the highest expression level in leaves, far higher than that in root, stem and flower. HPLC analysis showed that the scutellarin was the highest in leaves, followed by the flowers and stems, scutellarin was not detected in root.
Correlation analysis showed that CHS expression amount and scutellarin content in different parts of E. breviscapus is positive correlation (r = 0.761, P < 0.05), it suggests that CHS gene expression level has important effect on biosynthesis of scutellarin.
灯盏花中的灯盏乙素是一种具有显著药理活性的黄酮类化合物，其生物合成途径尚不完全清楚。查尔酮合酶（CHS）是调控黄酮类化合物生物合成的关键酶，本研究旨在通过研究灯盏花不同部位的CHS基因表达模式并结合灯盏乙素含量，来阐释基因表达模式与灯盏乙素含量之间的关系。
通过RT-PCR和RACE克隆CHS全长，并采用荧光定量PCR进行分析。采用HPLC分析组织中灯盏乙素的含量。
该基因全长序列为1270bp，编码405个氨基酸。软件分析发现该DNA序列与菊科植物同源盒基因的相似性为80%。荧光定量分析显示，CHS在叶中的表达水平最高，远高于根、茎和花中的表达水平。HPLC分析显示，叶中灯盏乙素含量最高，其次是花和茎，根中未检测到灯盏乙素。
相关性分析表明，灯盏花不同部位的CHS表达量与灯盏乙素含量呈正相关（r = 0.761，P < 0.05），提示CHS基因表达水平对灯盏乙素的生物合成具有重要影响。
