干旱胁迫下白沙蒿LEA基因的表达及序列分析  

Expression and sequence analysis of the LEA gene of Artemisia sphaerocephala under drought stress

作　　者：杜永婷 王铁娟[1] 杜俊瑞[1] 陈静 Yongting Du;Tiejuan Wang;Junrui Du;Jing Chen(College of Life Science and Technology,Inner Mongolia Normal University,Huhhot 010020,China)

机构地区：[1]内蒙古师范大学生命科学与技术学院,内蒙古呼和浩特010020

出　　处：《生物技术》2018年第4期318-322,371,共6页Biotechnology

基　　金：国家自然科学基金项目("蒿属两种固沙先锋植物的生态适应机制比较研究";No.31160130)

摘　　要：[目的]确定白沙蒿在干旱胁迫下起调节作用的LEA蛋白家族及其生物信息学特征。[方法]对在正常生长、中度胁迫和重度胁迫下的白沙蒿进行转录组测序,获得其LEA表达的差异性,对其中显著上调表达的基因进行序列分析。[结果]与多数报道的物种不同,白沙蒿在干旱胁迫时起调控作用的是第5家族LEA5蛋白。白沙蒿LEA的开放阅读框(ORF)全长264 bp,编码87个氨基酸。LEA5蛋白的分子量为9 406.74 Da,等电点为9.75,其序列与黄花蒿同源性最高(64%)。LEA蛋白为亲水性蛋白,定位于线粒体(73.9%),二级结构以无规则卷曲(59.77%)和α-螺旋(37.93%)为主,无信号肽和跨膜结构。[结论]白沙蒿在干旱胁迫下,LEA5参与了抗旱的调控,该基因的生物信息学特征分析为深入了解白沙蒿及蒿属其它固沙植物的抗旱机制提供一定的理论基础。[Objective] This paper aimed to confirm the LEA protein family and its bioinformatics characteristics of Artemisia sphaerocephala under drought stress. [Methods] The transcription sequencing of A. sphaerocephala were carried out under normal growth,moderate stress and severe stress,the difference of LEA expression was acquired,and then significantly up-regulated gene was analyzed. [Results] Unlike most reported species,the LEA5 protein played a regulatory role in A. sphaerocephala under drought stress. The open reading frame（ ORF） of the gene was 264 bp in length and encoded a protein of 87 amino acids. The estimated molecular weight and the theoretical PI were 9 406. 74 Da and 9. 75,respectively. Its sequence has the highest homology（ 91%） with LEA5 protein of A. annua. The LEA protein of A. sphaerocephala was predicted as a hydrophilic protein,located in the mitochondria（ 73. 9%）,mainly composed of random curl（ 59. 77%） and α-helix（ 37. 93%） in the secondary structure,without signaling peptide and transmembrane structure. [Conclusion] Under drought stress,LEA5 protein of A. sphaerocephala participated in the regulation of drought resistance. The analysis on bioinformatics features of LEA5 gene provides a theoretical basis for understanding the mechanism of drought resistance for A. sphaerocephala and other sand-fixing plants of Artemisia.

关 键 词：白沙蒿 干旱胁迫处理 胚胎发育晚期丰富蛋白 生物信息学分析 

分 类 号：Q71[生物学—分子生物学]