小麦尿卟啉原Ⅲ合成酶基因克隆及序列分析  

Cloning and Sequence Analysis of Uroporphyrinogen Ⅲ Synthase Gene in Wheat

作　　者：曹凤[1] 王亚红[1] 金伟波[1] 杜光源[1] 郭蔼光[1] 

机构地区：[1]西北农林科技大学生命科学学院

出　　处：《西北植物学报》2007年第7期1299-1304,共6页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家转基因植物研究与产业化开发专项(JY03A-11-01)

摘　　要：根据水稻已公布的尿卟啉原Ⅲ合成酶(UROS)基因和小麦EST的保守序列,设计特异性引物对小麦尿卟啉原Ⅲ合成酶基因的部分片段进行克隆,得到了364 bp的cDNA(命名为UROS1)。以UROS1作为种子进行电子克隆,得到一段长为1210 bp的cDNA序列,并设计特异性引物克隆到1个1077 bp cDNA序列。对该片段分析结果表明,克隆得到的小麦UROS基因包含了信号肽区和全长的成熟肽区。小麦UROS基因与水稻UROS基因的同源性为86%左右,其推导氨基酸序列与水稻和拟南芥蛋白序列同源性分别约91%和79%。动物、植物以及微生物间核酸序列的保守性较低,氨基酸序列保守性也不高,但都存在UROS保守结构域(Hem D)。进化分析显示,该酶在不同物种间的进化速度差异较大。A 364 bp cDNA fragment was amplified from cDNA transcriped from the total RNA of wheat using a pair of specific primers,which were designed at the highly conserved regions according to the wheat ESTs and the rice UROS gene. Taking the 364 bp cDNA fragment as querying sequence,5 highly homologous ESTs were found at the wheat EST database by Local Blast and then a 1 210 bp contig with the full ORF of UROS gene was assembled. Another pair of specific primer were designed according to this assembled contig and a specific 1 077 bp cDNA fragment was amplified. The 1 077 bp fragment was then cloned and sequenced. The cDNA sequence was disparate among different species. However,the protein had a conserved domain Hem D,or HEM 4,though the amino acid sequence shows little homolog in differrent species. The phylogenic analysis suggests that the UROS gene is disparate in the evolutionary.

关 键 词：小麦返白系 尿卟啉原Ⅲ合成酶 电子克隆 序列分析 

分 类 号：Q78[生物学—分子生物学]