摘要
[目的]本研究旨在为盐碱环境下分析羊草耐受性分子机制提供理论基础。[方法]以羊草(Leymus chinensis)的EST(expressed sequence tags,ESTs)序列作为克隆的基础,采用能从低丰度转录本中快速克隆出cDNA的5’及3’末端的RACE技术,获得羊草GST基因(LcGST),并利用生物信息学软件对该基因进行分析。[结果]克隆获得基因全长为833 bp的LcGST基因序列,该基因存在645 bp的开放读码框,编码的蛋白为217个氨基酸构成的稳定弱酸性亲水蛋白,其分子量大小为24.78 kDa。羊草LcGST蛋白预测具有4个磷酸化修饰位点,不具有糖基化修饰位点。也不含有信号肽结构和跨膜结构域,但拥有两个典型的GST保守结构域。其二级结构和三级结构以α螺旋为主,伴以少量β折叠。进化关系中,羊草与二穗短柄草最近,次之为日本稻和小米,与菠萝和番茄是进化关系最远的。[结论]本研究发现的羊草GST蛋白的理化性质及对其功能结构域的分析有助于为GST基因应用于植物的耐盐碱优良性状的改良奠定基础。
[Objective]The present study was aimed to provide a theoretical basis for analyzing the molecular mechanism of Leymus chinensis tolerance to saline and alkali stresses.[Methods]EST(expressed sequence tags)sequences of Leymus chinensis were used as the basis for gene cloning,and RACE techniques that can quickly clone the 5’and 3’ends of cDNA from lowabundance transcripts was used to obtain L.chinensis GST genes(LcGST).The obtained genes were analyzed using bioinformatics software.[Result]The LcGST gene sequence with a total length of 833 bp was cloned and the gene had an open reading frame(ORF)of 645 bp.The encoded protein was a stable weak acidic hydrophilic protein containing 217 amino acids,and its molecular weight was 24.78 kDa.The LcGST protein of Leymus chinensis was predicted to have 4 phosphorylation modification sites and no glycosylation modification sites.It did not contain signal peptide structure and transmembrane domain,but possessed two typical GST conserved domains.Its secondary and tertiary structures were predominantlyα-helixes,accompanied by a small amount ofβ-sheets.The evolutionary relationship between L.chinensis and Brachypodium distachyon was the closest,followed by Oryza sativa Japonica Group and Setaria italica,while Ananas comosus and Solanum ycopersicum displayed the farthest evolutionary relationship to L.chinensis.[Conclusion]The physical and chemical properties of L.chinensis GST protein discovered in this study help to lay a foundation for the further application of GST gene to improve the salt-tolerant and excellent traits of plants.
作者
邢磊
郭园艺
汪自庆
麻鹏达
Xing Lei;Guo Yuanyi;Wang Ziqing;Ma Pengda(College of Science,Northwest A&F University college of science,Yangling 712100,China;College of Lifescience,Northwest A&F University college of science,Yangling 712100,China)
出处
《山西农业大学学报（自然科学版）》
CAS
北大核心
2020年第5期48-56,共9页
Journal of Shanxi Agricultural University(Natural Science Edition)
基金
中央高校基本科研业务费专项基金项目(2452018150)。
