拟南芥TUA2参与ABA胁迫下的种子萌发过程  

Arabidopsis TUA2 Gene Mediates Seed Germination Under ABA Stress

作　　者：刘海浩[1] 吴立柱 岳智亮[1] 潘延云[1] 

机构地区：[1]河北农业大学生命科学学院,河北保定071000

出　　处：《中国农业科学》2012年第21期4343-4350,共8页Scientia Agricultura Sinica

基　　金：国家自然科学基金项目(30570993);河北省自然科学基金项目(C2008000292)

摘　　要：【目的】利用反向遗传学研究拟南芥TUA2与ABA途径相关基因的相互关系以及对种子萌发的影响。【方法】采用PCR、Tail PCR和RT-PCR技术对来自ABRC的T-DNA插入TUA2突变体进行插入位点的鉴定和转录活性的分析;利用转基因技术获得TUA2超表达植株;检测了含不同浓度ABA的MS培养基中各突变体和TUA2超表达植株的种子萌发;通过RT-PCR检测了突变体中ABA途径相关基因HAB、ABI1、RD22和P5CS的表达变化。【结果】突变体tua2-1和tua2-2的T-DNA插入位点均位于TUA2的启动子区,且二者的TUA2表达量均升高。在含有ABA(0.8μmol.L-1)的MS培养基中,突变体和转基因等5个株系的种子萌发延迟,播种第5天萌发率在6%—18%,相同条件下的野生型种子萌发率为76%;ABI1和HAB在TUA2超表达体中的表达明显低于野生型,受ABA诱导后被诱导表达的程度也远低于野生型。【结论】TUA2可能参与了ABA信号途径对种子萌发过程的调节。【Objective】This study would characterize the TUA2 gene involving in seed germination under ABA stress in Arabidopsis by the method of reverse genetics. 【Method】 The Arabidopsis T-DNA inserted into TUA2 gene mutants were obtained from ABRC. The T-DNA insertion sites of mutants were analyzed by Tail PCR. Over-expression constructs of TUA2 were introduced into Arabidopsis by an Agrobacterium-mediated method. RT-PCR was used to detect TUA2 and ABA-responsive genes accumulation in mutants and transgenic plants. The seed germination of transgenic and mutant lines was tested on MS medium with different concentrations of ABA. 【Result】 The T-DNA was inserted into the gene promoter region in mutants tua2-1 and tua2-2, and led to the increasing accumulation of the TUA2. In the medium of MS/0.8 μmol？L-1 ABA, the seed germination rate of wild type was 76% after five days, whereas all the TUA2 over-expression lines, mutants and transgenic plants, were 6%-18%. The expression of ABII, HAB and P5CS was induced by ABA in wild type, but not in mutants and transgenics. 【Conclusion】 The T-DNA insertion of the mutants tua2-1 and tua2-2 resulted in the increasing expression of TUA2 gene. The TUA2 gene might be involved in plant responses to ABA by mediating the transcription of ABA-responsive genes.

关 键 词：拟南芥 种子萌发 TUA2 ABA 

分 类 号：Q945[生物学—植物学]