摘要
肉桂酸-4-羟化酶(C4H)、4-香豆酸-辅酶A(4CL)是烟草苯丙烷代谢途径的关键酶,其多酚类产物与烟草品质密切相关。本研究以酚类物质含量合成差异较大的2个烤烟品种红花大金元(HD)和K326为试验材料,利用同源克隆技术获得这2种烟草Ntc4h和Nt4cl基因的cDNA序列并进行表达特性分析。结果表明,在2个品种中Ntc4h和Nt4cl各有2个同源基因,Ntc4h1、Ntc4h2、Nt4cl1和Nt4cl2的ORF长度分别为1518 bp、1518 bp、1644 bp和1629 bp。Nt4cl1、Ntc4h1和Ntc4h2在编码序列上存在品种间差异。实时荧光定量PCR分析结果表明,该2种酶的基因在烟草中具有明显的时空表达特异性,2种酶基因在根、茎、叶、花和萼片中都有表达,在茎的木质部和韧皮部中的表达量均显著高于其他组织;在圆顶期和适熟期表达水平较高,在适熟期达到最高;且两品种中的表达模式存在差异。
Cinnamic acid-4-hydroxylase（ C4H） and ρ-coumaric acid-4-ligase（ 4CL） are the key enzymes in phenylpropanoid metabolic pathway,whose polyphenol products are corresponding to the quality of tobaccos. In the study,cDNAs of these two enzymes were obtained using homology-based cloning from variety honghua dajinyuan（ HD） and variety K326,whose quantity of polyphenol products differed significantly and their expression profiles were analyzed by real time qRT-PCR. The results showed that Ntc4 h and Nt4 cl both had two homologous genes. The ORF length of Ntc4h1,Ntc4h2,Nt4cl1,and Nt4cl2 was1518 bp,1518 bp,1644 bp,and 1629 bp,respectively. According to the analysis,Ntc4h1,Nt4cl1,and Ntc4h2 showed different coding sequence in these two varieties. Real time qRT- PCR analysis showed that all the genes specifically expressed in a spatial and temporal manner and the expression profiles differed in two varieties. The genes all expressed in root,stem,leaf,flower,and sepal with the expression of xylem and phloem were higher than others. The expression in fast growing stage and technical maturity stage was higher than the others with the highest in technical maturity stage.
出处
《植物遗传资源学报》
CAS
CSCD
北大核心
2014年第5期1067-1073,共7页
Journal of Plant Genetic Resources
基金
中国烟草总公司创新平台项目(201211)
中国烟草总公司重大专项(TS-06-20110038)
