【作者】 王大海； 苏晓华； 张冰玉； 黄秦军； 张香华；

【Author】 Wang Dahai Su Xiaohua Zhang Bingyu Huang Qinjun Zhang Xianghua (Research Institute of Forestry, Key Laboratory of Tree Breeding and Cultivation, State Forestry Administration, CAF Beijing 100091)

【机构】 中国林业科学研究院林业研究所；

【摘要】 根据美洲黑杨PdZFR部分cDNA序列采用RACE和拟基因组文库步行法克隆了该基因全长cDNA和基因组上全长片段。该基因开放编码框由615个碱基组成,编码205个氨基酸组成的多肽,其等电点为6.94,MW为24.37kD。通过Blastx软件对GenBank的nr数据库进行比对,该基因与拟南芥C3HC4-type ZF-RING同源性达86%。对PdZFR基因转录、剪切分析表明,该基因包含9个内含子和10个外显子,剪切出的内含子两端趋于保守,为’AG’和’GT’,外显子平均长度较内含子短,属于I类内含子。该基因转录起始碱基为G(+1,1817),无明显真核生物启动子核心序列TATA框,从+1(1817)到+13(1830)区域A/T含量明显较高。该基因转录终止位置,存在大量重复序列,有利于在转录过程中形成局部二级结构,调节基因转录终止。基因组上分布分析表明,该基因位于杨树基因组LG_VI上对应物理位置的16611332-16616623之间,并在杨树基因组LG_XVIII上有部分同源序列。各部位表达分析表明,该基因与植物发育和次生生长有关。更多还原

【Abstract】 The cloning of PdZFR in cDNA pool and on genome of poplar, were carried out according to the partial cDNA sequence of gene, which was screened out from developing xylem using cDNA micro-array technology before. The open read frame of this gene is consisted of 615 nucleotides encoding a peptide of 205 amino acids, which has pI of 6.94 and MW of 24.37kD. The gene shares 86% similar sequence with C3HC4-type ZF-RING from Arabidopsis thaliana according to the searching result in nr library. The splicing pattern of PdZFR shows that this gene is consisted of 10 exons and 9 introns which classified as Class I, and the two ends of introns are conserved, which are ‘AG’ and ‘GT’. The start nucleotide of transcription is G and the core sequence of eukaryotic promoter, named TATA box was not found. However, the region ranged from +1 to +13 has high content of A/T. Around the transcription terminator, many repeated sequences, presumed as transcription termination signal, are existed. The blast result of PdZFR on genome shows that this gene is located on LG_VI ranged from 16611332 to 16616623 and has homological sequences on LG_XVIII. Expression pattern of PdZFR at different parts of poplar was also detected, and the conclusion obtained is that PdZFR related to secondary growth and development.更多还原