title: Production of oleanane-type sapogenin in transgenic rice via expression of β-amyrin synthase gene from Panax japonicus C. A. Mey.
abstract: BACKGROUND
  Panax japonicus C. A. Mey. is a rare traditional Chinese herbal medicine that uses ginsenosides as its main active ingredient. Rice does not produce ginsenosides because it lacks a key rate-limiting enzyme (β-amyrin synthase, βAS); however, it produces a secondary metabolite, 2,3-oxidosqualene, which is a precursor for ginsenoside biosynthesis.
  
  
  RESULTS
  In the present study, the P. japonicus βAS gene was transformed into the rice cultivar 'Taijing 9' using an Agrobacterium-mediated approach, resulting in 68 rice transgenic plants of the T0 generation. Transfer-DNA (T-DNA) insertion sites in homozygous lines of the T2 generation were determined by using high-efficiency thermal asymmetric interlaced PCR (hiTAIL-PCR) and were found to vary among the tested lines. Approximately 1-2 copies of the βAS gene were detected in transgenic rice plants. Real-time PCR and Western blotting analyses showed that the transformed βAS gene could be overexpressed and β-amyrin synthase could be expressed in rice. HPLC analysis showed that the concentration of oleanane-type sapogenin oleanolic acid in transgenic rice was 8.3-11.5 mg/100 g dw.
  
  
  CONCLUSIONS
  The current study is the first report on the transformation of P. japonicus βAS gene into rice. We have successfully produced a new rice germplasm, "ginseng rice", which produces oleanane-type sapogenin.
authors.affiliation: College of Food Science, Fujian Agriculture and Forestry University, 15 Shangxiadian Road, CangShan District, Fuzhou, 350002, Fujian, China. hzwfau@163.com.|Agricultural Product Quality Institute, Fujian Agriculture and Forestry University, 15 Shangxiadian Road, CangShan District, Fuzhou, 350002, Fujian, China. hzwfau@163.com.
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Huang
authors.affiliation: Agricultural Product Quality Institute, Fujian Agriculture and Forestry University, 15 Shangxiadian Road, CangShan District, Fuzhou, 350002, Fujian, China. linjc2011@126.com.
authors.forename: Juncheng
authors.initials: J
authors.lastname: Lin
authors.affiliation: Agricultural Product Quality Institute, Fujian Agriculture and Forestry University, 15 Shangxiadian Road, CangShan District, Fuzhou, 350002, Fujian, China. chengzuxin@163.com.
authors.forename: Zuxin
authors.initials: Z
authors.lastname: Cheng
authors.affiliation: Agricultural Product Quality Institute, Fujian Agriculture and Forestry University, 15 Shangxiadian Road, CangShan District, Fuzhou, 350002, Fujian, China. xmfau@163.com.
authors.forename: Ming
authors.initials: M
authors.lastname: Xu
authors.affiliation: Agricultural Product Quality Institute, Fujian Agriculture and Forestry University, 15 Shangxiadian Road, CangShan District, Fuzhou, 350002, Fujian, China. 115942082@qq.com.
authors.forename: Mingshu
authors.initials: M
authors.lastname: Guo
authors.affiliation: Agricultural Product Quality Institute, Fujian Agriculture and Forestry University, 15 Shangxiadian Road, CangShan District, Fuzhou, 350002, Fujian, China. 764900262@qq.com.
authors.forename: Xinying
authors.initials: X
authors.lastname: Huang
authors.affiliation: Agricultural Product Quality Institute, Fujian Agriculture and Forestry University, 15 Shangxiadian Road, CangShan District, Fuzhou, 350002, Fujian, China. yangzj41@163.com.
authors.forename: Zhijian
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Agricultural Product Quality Institute, Fujian Agriculture and Forestry University, 15 Shangxiadian Road, CangShan District, Fuzhou, 350002, Fujian, China. zjg231@126.com.
authors.forename: Jingui
authors.initials: J
authors.lastname: Zheng
mesh_terms: D004269:DNA, Bacterial / Q000378:metabolism; D019751:Intramolecular Transferases / Q000235:genetics / Q000378:metabolism*; D009828:Oleanolic Acid / Q000031:analogs & derivatives* / Q000096:biosynthesis; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D005894:Panax / Q000201:enzymology* / Q000235:genetics; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D010957:Plasmids / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D010940:Plant Proteins; C036483:T-DNA; C413246:oleanane; D009828:Oleanolic Acid; D019751:Intramolecular Transferases; C039924:2,3-oxidosqualene-beta-amyrin-cyclase