摘要
【目的】对蒺藜苜蓿ROP基因进行克隆与表达分析,为深入研究ROP基因在豆科植物与根瘤菌共生互作过程中的功能提供理论依据。【方法】依据拟南芥11个ROP保守序列特征和蒺藜苜蓿数据库信息,同源克隆蒺藜苜蓿的MtROP9基因,采用生物信息学方法对该基因序列进行分析,并采用半定量RT-PCR法,对MtROP9基因在蒺藜苜蓿不同组织及根瘤菌侵染后不同时间根系中的表达水平进行检测。【结果】从蒺藜苜蓿根系中克隆到了MtROP9基因的cDNA序列,全长为947 bp,编码209个氨基酸。序列分析表明,MtROP9具有ROP蛋白典型的结构特征,并与拟南芥AtROP9、水稻OsRac2、葡萄VvROP9、玉米ZmROP6和ZmROP7具有高度的相似性。MtROP9基因具有一定的时空表达特性,在根系和花中表达水平较高,在茎和根瘤中表达水平相对较低,在叶中几乎不表达。在蒺藜苜蓿与根瘤菌共生互作的早期,MtROP9基因能够被根瘤菌侵染诱导表达,在根瘤菌诱导处理不同时间的根系表达水平不同。【结论】克隆了蒺藜苜蓿小G蛋白MtROP9基因。MtROP9基因可能参与了豆科植物与根瘤菌共生互作早期信号的调控。
【Objective】The objective of this study was to isolate ROP（RhoGTPase of plant） gene in Medicago truncatula and analyze its expression pattern in order to further investigate the function of ROP gene in the process of symbiotic interaction between host legume plant and Rhizobium.【Method】Based on the conserved sequences of 11 ROP proteins in Arabidopsis,homologous gene in Medicago truncatula was isolated by RT-PCR.The sequence analysis of MtROP9 was carried out using the method of bioinformation.Using the method of Semi-quantitative RT-PCR,the expression levels of MtROP9 was detected in different tissues and in inoculated root on different time of post-inoculation.【Result】A full-length 947 bp cDNA sequences of MtROP9 gene that coded 209 amino acids were isolated from root of Medicago truncatula.Results of sequence analysis showed MtROP9 contained the typical structures of ROP GTPase protein.Homologous comparison with some plant ROPs indicated that MtROP9 shared high similarity in amino acid sequence with AtROP9,OsRac2,VvROP9,ZmROP6 and ZmROP7 respectively.Spatial and temporal patterns of MtROP9 gene were approved through detected expression levels of MtROP9 in different tissues and in inoculated root by Rhizobium.MtROP9 was expressed preferentially in root and flower,and showed lower expression levels in stem and nodule.But MtROP9 almost could not be detected in leaf.Expression of MtROP9 could be induced by inoculation of Rhizobium.MtROP9 gene displayed a varied expression level in inoculated root during different time of post-inoculation by Rm1021.【Conclusion】A small GTPase MtROP9 gene in Medicago truncatula was obtained.MtROP9 gene may involve in the regulation of signal transduction that occurred on early stage of symbiotic interaction between legume plant and Rhizobium.
出处
《西北农林科技大学学报（自然科学版）》
CSCD
北大核心
2009年第6期210-216,共7页
Journal of Northwest A&F University(Natural Science Edition)
基金
新疆生产建设兵团绿洲生态农业重点实验室开放课题(200503)
