Abstract:

Two cDNAs encoding cinnamate 4-hydroxylase homologues were isolated from Gossypium arboreum L. by PCR-mediated method using a primer based on a conserved region of plant cytochrome P450. The two cotton P450s belong to the subfamily of CYP73A, and were named CYP73A25 and CYP73A26, respectively. Both the cDNAs encode proteins of 505 amino acid residues, showing 91.3% sequence identity with each other. Their sequence identities with C4Hs of other dicotyledon plants may be as high as 90%. RT-PCR analysis indicated that CYP73A26 was clearly expressed in sepals, petals, peels and seeds during development. For CYP73A25, while a significant level of transcripts was detected in sepals, petals and peels, the level in developing seeds was either weak, or undetectable.

亚洲棉C4H同源cDNA的分离和表达特征分析
骆萍 王国栋 陈晓亚*

（中国科学院上海生命科学研究院植物生理生态研究所，植物分子遗传国家重点实验室，上海200032）

摘要： 根据P45 0保守序列设计简并引物 ,从亚洲棉 (Gossypiumarboreum L .)cDNA文库中分离到两个肉桂酸-4-羟化酶 (C4H)同源cDNA克隆。这两个棉花P45 0被划分到CYP73A亚族中 ,分别被命名为CYP73A2 5和CYP73A2 6。它们各编码 5 0 5个氨基酸残基 ,彼此之间的氨基酸序列同源性为 91.3%。它们与其他植物C4H的同源性高达 90 %以上。RT_PCR分析表明 ,CYP73A2 6在棉花的花瓣、花萼果皮及发育种子中均有较高水平的表达。CYP73A2 5在花瓣、花萼和果皮中有较强表达 ,而在种子中表达很弱
 

关键词： 肉桂酸-4-羟化酶；棉花；亚洲棉；P450

Key words: cinnamate 4-hydroxylase, cotton, Gossypium arboreum, P450