摘要
用烟草花叶病毒弱毒株系N14预先接种,可以诱导烟草对病原真菌赤星病菌的系统获得性抗性(SAR),减轻病菌引起的赤星病。选择表现诱导抗性最强植株材料进行组织培养与植株再生,通过体细胞无性系变异增强和巩固SAR性状,获得SAR组成性表达的突变体(constitutive expresser of SAR)ces2-1。除了抗病表型,ces2-1还组成性表达多种防卫反应基因。回交实验与遗传分析表明,ces2-1是在野生型位点上的单基因显性突变。对ces2-1与野生型进行mRNA差异显示分析,得到一个ces2-1独有、在野生型中缺少的转录本,与前人报道的烟草受过氧化氢诱导的一个基因片段同源。用cDNA末端快速扩增技术克隆了这个转录本的全长序列,根据生物信息学分析与功能的初步测定,把这个基因命名为烟草受过氧化氢诱导的抗病相关基因(hydrogen peroxide-induced1,NtHPI1)。
Inoculation of tobacco （Nicotiana tabacum） with the hypovirulent strain N14 of tobacco mosaic virus induced the plant to develop systemic acquired resistance （SAR） against Alternaria alternata, a fungal pathogen that causes brown spot in tobacco. After a somaclonal variation protocol was applied to leaf discs from resistant plants, regenerated plants were screened for constitutive expresser of SAR. This protocol yielded a mutant designated as ces2-1. In ces2-1, resistance to the pathogen no longer required induction treatment, and the expression of several defense resistance genes, such as PR-1 a and ChiaS, also became constitutive. Genetic analyses of the backcross revealed that ces2-1 re- presents a disruption at a single gene and is dominant in heredity over the WT locus. The profile of differentially expressed cDNA identified a transcript highly identical with a hydrogen peroxide-induced cDNA fragment already isolated from tobacco. The transcript was present in ces2-1 but absent in WT and was thus considered important in resistance. Full length of the transcript gene was cloned by a rapid amplification of cDNA end protocol and named NtHPI1 based on bioinformatics and experimental analyses.
出处
《云南农业大学学报（自然科学版）》
CAS
CSCD
北大核心
2009年第4期497-507,共11页
Journal of Yunnan Agricultural University:Natural Science
基金
国家自然科学基金(30771441)
