摘要
为了深入研究植物耐铵盐胁迫的分子机制,本研究采用液体培养与蛭石培养相结合的方法,在拟南芥哥伦比亚野生型的EMS诱变突变体库中筛选获得耐铵且耐盐胁迫的株系,并研究了高铵与盐胁迫条件下,氮素同化关键酶谷氨酰胺合成酶基因(AtGLN)家族6个成员的表达特征,对AtGLN家族成员氨基酸序列与启动子元件进行初步分析。结果表明,高铵与盐胁迫条件下,与野生型相比,突变体受到的抑制程度较小,种子萌发率较高,幼苗单株鲜重较大,说明筛选出的突变体在种子萌发阶段和幼苗期,具有耐铵与耐盐胁迫特性;qPCR结果显示,在高铵条件下突变株幼苗AtGLN1;1、AtGLN1;4的表达显著上调,而AtGLN2与野生型相比维持了相对较高的基因表达水平,与其耐铵性成正相关;在盐胁迫条件下,突变株AtGLN1;2与AtGLN2维持相对较高的基因表达水平,与其耐盐性正相关;对AtGLN基因家族的基因启动子的分析揭示其具有响应光、干旱、ABA等的顺式作用元件,揭示该基因家族与植物的生长发育及逆境胁迫响应相关。本研究为后续深入揭示植物的耐铵盐机制,进一步筛选和培育耐铵种质提供了依据。
In order to further study the molecular mechanism of plant tolerance to ammonium salt stress in this study,we used a combination of liquid culture and vermiculite culture to screen and obtain ammonium-and salinity-tolerant strains from the Arabidopsis'Colombia'wild-type EMS mutant library.Gene expression characteristics of six members of the glutamine synthetase(AtGLN)family,which encode a key enzyme in nitrogen assimilation,were studied under high ammonium and salt stress conditions,and the amino acid sequences and promoter elements of AtGLN family members were preliminarily analyzed.The results showed that under the conditions of high ammonium and salt stress,the seedlings with high ammonium tolerance were less inhibited,with higher rate in fresh weight and seed germination,which indicates that the screened mutants have the tolerance to ammonium and salt stress at the seed germination stage and seedling stage.The results of qPCR showed that the expression of AtGLN1;1,AtGLN1;4,in mutant seedlings was significantly up-regulated under high ammonium conditions.AtGLN2 maintains a relatively high gene expression level compared with wild type,which is positively correlated with its ammonium tolerance,which was positively correlated with its ammonium tolerance.Under salt stress conditions,AtGLN1;2 and AtGLN2 maintained a higher gene expression level in mutants,which were positively correlated with their salt tolerance.Analysis of gene promoters of AtGLN gene family revealed that it has cis-acting elements that respond to light,drought,ABA,etc.,which may be related to plant growth and development and the response to stress.This study lays a foundation for further revealing the mechanism of high ammonium tolerance of plants and further screening and breeding of ammonium tolerant germplasm.
作者
张春丹
郑中尧
刘聪
张园清
刘坤祥
徐虹
Zhang Chundan;Zheng Zhongyao;Liu Cong;Zhang Yuanqing;Liu Kunxiang;Xu Hong(College of Life Sciences,Northwest A&F University,Yangling,712100)
出处
《分子植物育种》
CAS
北大核心
2022年第18期6057-6066,共10页
Molecular Plant Breeding
基金
国家自然科学基金面上项目(32170270)资助。
关键词
拟南芥
高铵胁迫
盐胁迫
谷氨酰胺合成酶基因
Arabidopsis
High ammonium stress
Salt stress
Glutamine synthase gene
