Zhiqing Wang1, Haiqin Ma2, Min Zhang3, Ziqing Wang2, Yixin Tian3, Wei Li4, Yingping Wang4. 1. Laboratory of Cultivation and Breeding of Medicinal Plants, National Administration of Traditional Chinese Medicine, College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, 130118, Jilin, China. wangzhiqing96@sohu.com. 2. Institute of Special Wild Economic Animals and Plants, Chinese Academy of Agriculture Sciences, Changchun, 130112, Jilin, China. 3. Laboratory of Cultivation and Breeding of Medicinal Plants, National Administration of Traditional Chinese Medicine, College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, 130118, Jilin, China. 4. State & Local Joint Engineering Research Center of Ginseng Breeding and Application, College of Chinese Medicinal Materials, Jilin Agricultural University, Changchun, 130118, Jilin, China.
Abstract
BACKGROUND: Asarum heterotropides Fr. Schmidt var. mandshuricum (Maxim.) Kitag. is an important medicinal and industrial plant, which is used in the treatment of various diseases. The main bioactive ingredient is the volatile oil having more than 82 identified components of which methyleugenol, safrole, myristicin, and toluene account for about 70% of the total volume. As a sciophyte plant, the amount of light it absorbs through leaves is an important factor for growth and metabolism. RESULTS: We grew Asarum plants under full, 50, 28, and 12% sunlight conditions to investigate the effect of different light irradiances on the four major volatile oil components. We employed de novo transcriptome sequencing to understand the transcriptional behavior of Asarum leaves regarding the biosynthetic pathways of the four volatile oil components, photosynthesis and biomass accumulation, and hormone signaling. Our results demonstrated that the increasing light conditions promoted higher percent of the four components. Under full sunlight conditions, cinnamyl alcohol dehydrogenase and cytochrome p450719As were upregulated and led the increased methyleugenol, safrole, and myristicin. The transcriptomic data also showed that Asarum leaves, under full sunlight conditions, adjust their photosynthesis-antenna proteins as a photoprotective response with the help of carotenoids. Plant hormone-signaling related genes were also differentially expressed between full sunlight and low light conditions. CONCLUSIONS: High light induces accumulation of major bioactive ingredients A. heterotropides volatile oil and this is ascribed to upregulation of key genes such as cinnamyl alcohol dehydrogenase and cytochrome p450719As. The transcriptome data presented here lays the foundation of further understanding of light responses in sciophytes and provides guidance for increasing bioactive molecules in Asarum.
BACKGROUND: Asarum heterotropides Fr. Schmidt var. mandshuricum (Maxim.) Kitag. is an important medicinal and industrial plant, which is used in the treatment of various diseases. The main bioactive ingredient is the volatile oil having more than 82 identified components of which methyleugenol, safrole, myristicin, and toluene account for about 70% of the total volume. As a sciophyte plant, the amount of light it absorbs through leaves is an important factor for growth and metabolism. RESULTS: We grew Asarum plants under full, 50, 28, and 12% sunlight conditions to investigate the effect of different light irradiances on the four major volatile oil components. We employed de novo transcriptome sequencing to understand the transcriptional behavior of Asarum leaves regarding the biosynthetic pathways of the four volatile oil components, photosynthesis and biomass accumulation, and hormone signaling. Our results demonstrated that the increasing light conditions promoted higher percent of the four components. Under full sunlight conditions, cinnamyl alcohol dehydrogenase and cytochrome p450719As were upregulated and led the increased methyleugenol, safrole, and myristicin. The transcriptomic data also showed that Asarum leaves, under full sunlight conditions, adjust their photosynthesis-antenna proteins as a photoprotective response with the help of carotenoids. Plant hormone-signaling related genes were also differentially expressed between full sunlight and low light conditions. CONCLUSIONS: High light induces accumulation of major bioactive ingredients A. heterotropides volatile oil and this is ascribed to upregulation of key genes such as cinnamyl alcohol dehydrogenase and cytochrome p450719As. The transcriptome data presented here lays the foundation of further understanding of light responses in sciophytes and provides guidance for increasing bioactive molecules in Asarum.
Authors: Claire E Hutchison; Jie Li; Cristiana Argueso; Monica Gonzalez; Eurie Lee; Michael W Lewis; Bridey B Maxwell; Tony D Perdue; G Eric Schaller; Jose M Alonso; Joseph R Ecker; Joseph J Kieber Journal: Plant Cell Date: 2006-11-22 Impact factor: 11.277
Authors: Eugene V Koonin; Natalie D Fedorova; John D Jackson; Aviva R Jacobs; Dmitri M Krylov; Kira S Makarova; Raja Mazumder; Sergei L Mekhedov; Anastasia N Nikolskaya; B Sridhar Rao; Igor B Rogozin; Sergei Smirnov; Alexander V Sorokin; Alexander V Sverdlov; Sona Vasudevan; Yuri I Wolf; Jodie J Yin; Darren A Natale Journal: Genome Biol Date: 2004-01-15 Impact factor: 13.583