摘要
[目的]本文旨在研究植物登陆过程中,植物细胞中囊泡拴系因子复合体exocyst的亚基复制、变异和分化的过程和规律,探索其在植物适应陆地环境中的意义。[方法]以7种代表性的藻类和9种代表性的陆生植物的exocyst复合体亚基序列为基础,采用序列比对、进化分析、保守基序鉴定以及高级结构预测的方法,研究植物登陆过程中,exocyst复合物的不同亚基基因复制、变异及结构演化规律,并以拟南芥为陆生植物代表验证其特有的GroupⅢExo70亚基(Exo70G)的亚细胞定位及其基因在干旱和盐胁迫下的表达。[结果]exocyst复合体的内部亚基(Sec3、Sec5、Sec6、Sec8、Sec10和Sec15)在藻类和陆生植物中拷贝数低且序列高度相似,没有显著变化。2个表面亚基(Exo84和Exo70)在登陆过程中,通过复制和变异导致多样化,特别是Exo70亚基中分化产生陆生植物特有的GroupⅢ类群亚基,其定位在反式高尔基体网络上,在干旱胁迫和盐胁迫下高表达。[结论]登陆过程中,植物exocyst内部亚基的数量及结构并没有显著改变,但是exocyst表面亚基的数量及结构发生显著改变,特别是Exo70亚基分化出陆生植物特有的GroupⅢ(Exo70G)亚家族,对植物适应陆地干旱高盐的环境具有积极意义,是植物适应陆地环境的一种进化策略。
[Objectives]The purpose of this study was to investigate the vesicle tethering complex exocyst evolution process during plant terrestrialization,and to explore the significance of this process for land plants adapting to the environment.[Methods]Based on the amino acid sequences of exocyst subunits in seven typical algae and nine typical land plants,sequence alignment,evolution analysis and spatial structure prediction and comparative method were used to study the molecular evolution process of exocyst complex during plant terrestrialzation.Then Arabidopsis thaliana was used as an example to explore the land plant special exocyst subunits Exo70G subcellular localization and expression under drought and salt stress.[Results]During plant terresttrialzation,exocyst internal subunits(Sec3,Sec5,Sec6,Sec8,Sec10 and Sec15)in algae and terrestrial plants were highly conserved and did not significantly change,however,two surface subunits(Exo84 and Exo70),through replication and mutation led to diversification,especially land plants special Exo70G subunits were produced,which were localized on the trans-Golgi network(TGN),strongly expressed under drought stress and salt stress.[Conclusions]In the process of terresttrialzation,plants exocyst internal subunits showed no significant changes,however,the number and the structure of exocyst surface subunits were obviously changed,especially,the Exo70G subunit was produced.Exo70G expression responsed to drought and salt stress strongly.These results indicated that the plants adapting to land life under drought and high salt environment depended on Exo70G subunit.
作者
刘文龙
胡钢
周光磊
李炳君
吴冬杰
刘松奇
鲍依群
谭小云
LIU Wenlong;HU Gang;ZHOU Guanglei;LI Bingjun;WU Dongjie;LIU Songqi;BAO Yiqun;TAN Xiaoyun(College of Life Sciences,Nanjing Agricultural University,Nanjing 210095,China)
出处
《南京农业大学学报》
CAS
CSCD
北大核心
2023年第3期489-498,共10页
Journal of Nanjing Agricultural University
基金
国家自然科学基金项目(32070190)。
关键词
植物登陆
exocyst复合体
分子进化
囊泡运输
plant terrestrialization
exocyst complex
molecular evolution
vesicular trafficking