摘要
香豆酸3'-羟化酶(coumarate-3-hydroxylase,C3H)是绿原酸代谢途径中的关键酶之一。为了揭示甘薯绿原酸生物合成途径和挖掘绿原酸合成相关基因,本研究从甘薯中克隆一个C3H的同源基因IbC3H。该基因全长1656 bp,包含一个1530 bp的完整开放阅读框,编码509个氨基酸。IbC3H蛋白具有典型P450家族蛋白结构特征,与牵牛花(Ipomoea nil)、马铃薯(Solanum tuberosum)、浆果状椒(Capsicum baccatum)和烟草(Nicotiana attenuate)中相应蛋白的同源性分别达到97.2%、85.4%、84.8%和84.8%。IbC3H启动子序列中含有脱落酸、赤霉素、乙烯和干旱等多个激素和胁迫响应元件,以及髓细胞组织增生病毒癌基因同源物(MYB)、碱性螺旋-环-螺旋蛋白(bHLH)、和WRKY蛋白等转录因子结合元件。荧光定量PCR结果显示,IbC3H在甘薯叶片中表达量最高,在茎中次之,而在块根中的表达量最低,与甘薯不同组织绿原酸含量正相关。本研究结果为进一步揭示IbC3H在绿原酸生物合成中的功能提供了依据。
Coumarate-3-hydroxylase(C3H)is one of the key enzymes in chlorogenic acid metabolic pathway.In order to reveal the chlorogenic acid biosynthesis in Ipomoea batatas and mine the genes involved in its metabolic pathway,a C3H homologous gene named IbC3H was cloned in Ipomoea batatas.The full-length of IbC3H was 1656 bp,containing 1530 bp opening reading frame,and encoding 509 amino acids.IbC3H protein contained conserved CYP450 domain and motifs,shared 97.2%,85.4%,84.8%and 84.8%identity with C3H proteins from Ipomoea nil,Solanum tuberosum,Capsicum baccatum and Nicotiana attenuate.The promoter sequence of IbC3H contained some hormones and stress response elements such as abscisic acid,gibberellin,ethylene,drought response elements,as well as transcription factor binding elements such as v-myb myeloblastosis viral oncogene homolog(MYB),basic helix-loop-helix protein(bHLH),andWRKY binding elements.Fluorescence quantitative PCR results indicated that IbC3H was mainly expressed in leaves,followed by stems and weakly expressed in tuberous roots,and its expression was highly correlated with the accumulation of chlorogenic acid in Ipomoea batatas.The above results laid a foundation for further revealing the function of IbC3H in chlorogenic acid biosynthesis.
作者
徐靖
朱红林
林延慧
韩义胜
唐力琼
王新华
王效宁
Xu Jing;Zhu Honglin;Lin Yanhui;Han Yisheng;Tang Liqiong;Wang Xinhua;Wang Xiaoning(Scientific Observation Station for Gene Resources and Germplasm Creation of Hainan,Ministry of Agriculture,Key Laboratory of Crop Genetics and Breeding of Hainan Province,Institute of Cereal Crops,Hainan Academy of Agricultural Sciences,Haikou,571100)
出处
《分子植物育种》
CAS
CSCD
北大核心
2020年第10期3126-3131,共6页
Molecular Plant Breeding
基金
海南省科研院所技术开发专项项目(KYYS-2018-03)资助。
