缺铁胁迫对梨叶片中GA信号转导相关基因的影响  

Effect of Iron-deficiency on the Expression of GA Signal Transduction Related Genes in Leaf of ‘Dangshansuli’ Pear(Pyrus bretschneideri Rehd.)

作　　者：丁伟[1] 周葱[1] 刘超[1] 何家轩 贾兵[1] 朱立武[1] 

机构地区：[1]安徽农业大学园艺学院,合肥230036

出　　处：《西北植物学报》2015年第2期233-238,共6页Acta Botanica Boreali-Occidentalia Sinica

基　　金：国家梨产业技术体系项目(nycytx-29-12)

摘　　要：以不同程度缺铁的‘砀山酥梨’组培苗为实验材料,应用ELISA法测定叶片中内源GA含量,并依据NCBI上GA氧化酶GA2ox同源基因的保守序列,采用RACE技术克隆其基因全长,从梨基因组数据库中比对获得GA受体GID1的4个等位基因和DELLA蛋白的4个等位基因,通过实时RT-PCR分析GA2ox基因和GID1的4个等位基因和DELLA蛋白的4个等位基因的相对表达量,以探讨缺铁对梨叶片GA含量及其信号转导相关基因表达的影响。结果表明:(1)梨叶片中GA含量随着其缺铁程度的加重而增加。(2)克隆出梨叶片中GA2ox基因,其cDNA全长为1 014bp(GenBank登录号为KJ008976)。(3)GA2ox基因的表达量并未随梨缺铁程度增加而上升;GA受体GID1的4个等位基因相对表达量均随梨缺铁程度的加重而增加,其相对表达量与GA含量呈正相关关系;在DELLA蛋白的4个等位基因中,仅DELLA1相对表达量随着梨缺铁程度的加重而逐渐增加,说明DELLA1对缺铁胁迫最敏感。推测梨缺铁诱导了GA合成,但并没有促进活性GA向无活性GA转化。To investigate the relationship between the content of gibberellins（GA） and the expression of its signal transduction related genes in leaf of pear plant with different degree of iron-deficiency,we used the in vitro plantlets of ‘Dangshansuli’ pear（Pyrus bretschneideri Rehd.） cultured in agar medium treated with different concentration of Fe-EDTA as experiment material in this study.GA contents in leaf were tested by the Enzyme-Linked ImmunoSorbent Assay（ELISA）.According to the sequence of homologous gene from NCBI library,the full length of GA2ox gene was cloned by the method of the Rapid-amplification of cDNA Ends（RACE）.Four alleles of GID1 and DELLA blast from pear genome database.The levels of relative expression of GA2ox gene,four alleles of GID1 and DELLA were analyzed using real-time quantitative reverse transcription-PCR（qRT-PCR）.The results showed that：（1）The GA content in leaves increased as the iron content decreased in medium.（2）The full length of cDNA fragment of GA2ox gene cloned was 1 014 bp and had been submitted to the Genbank with the accession number of KJ008976.（3）The levels of relative expression of GA2ox gene at different degree of iron-deficiency did not increased as GA contents raised.The levels of relative expression of the four alleles of GID1 all increased as degree of iron-deficiency become severe.There were positive correlation between GA content and levels of relative expression of the four alleles of GID1.Only the levels of relative expression of DELLA1 increased as the degree of iron-deficiency become severe,that was most sensitive to the stress of iron-deficiency.It was speculated that the iron-deficiency could accelerate the synthesis of GA and would not promote active GA into inactive ones.

关 键 词：赤霉素 赤霉素氧化酶基因 赤霉素受体蛋白 赤霉素效应抑制蛋白 

分 类 号：Q785[生物学—分子生物学] Q789