草业科学2012，Vol.29Issue(10)：1546-1552,7.
3份高羊茅材料吡咯琳-5-羧酸合成酶基因的结构及酶活性比较
Characteristics of pyrroline-5-carboxylate synthetase genes and the enzyme activity in three Festuca arundinacea from Guizhou Province
摘要
Abstract
Pyrroline-5-carboxylate synthetase(P5CS) is the key enzyme in the proline synthesis from glutamate.As the main osmoregulation substance in plants,proline accumulation is positively correlated with the adaptability of plants to drought stress.Samples were chosen from three tall fescue(Festuca arundinacea) plants,Qiancao No.1(QC1),Qiancao No.2 with narrow leaf(QC2n) and broad leaf(QC2b).The upstream and downstream of P5CS genes from three samples were cloned by reverse transcription polymerase chain reaction(RT-PCR) method.The complete P5CS genes of QC1,QC2n and QC2b were spliced with open reading frame of 2 151 bp in length and encoded P5CS protein consisted of 717 amino acid residues.Compare to the known genes deposited in GenBank,the highest homology of P5CS genes from QC1,QC2n and QC2b with Puccinellia chinampoensis is 94%.Furthermore,six different amino acids were found from the Glu-5-kinase domain of the encoded P5CS protein among QC1,QC2n and QC2b samples,in which amino acids at site 37,85 and 142 were changed from hydrophobic residues into positively charged hydrophilic ones.The enzyme activities of P5CS and the proline content of leaves in sample QC1 were the highest and those of QC2b were the lowest.The results suggested that the amino acids changes in the Glu-5-kinase domain of P5CS might be pivotal for the enzyme activity,proline biosynthesis and the drought tolerance of F.arundinacea.关键词
高羊茅/P5CS基因/酶活性/脯氨酸/抗旱Key words
Festuca arundinacea/P5CS gene/enzyme activity/proline/drought resistance分类
农业科技引用本文复制引用
牛熙,冉雪琴,王嘉福,陈超..3份高羊茅材料吡咯琳-5-羧酸合成酶基因的结构及酶活性比较[J].草业科学,2012,29(10):1546-1552,7.基金项目
国家科技支撑计划 （）
贵州省科技创新人才团队建设专项 （）
贵州省科技厅农业攻关项目 （）
贵州大学研究生创新基金（校研农2011015）致谢：感谢贵州省草业研究所莫本田研究员提供的帮助. （）
