玉米淀粉分支酶基因启动子的克隆及生物信息学分析

Cloning and Bioinformatics Analysis of Promoter Sequence of Corn Starch Branching Enzyme Gene

[目的]为了研究不同淀粉含量的启动子之间是否有差异及对直链淀粉合成途径是否有影响。[方法]以常规玉米叶片基因组DNA为模板,利用NCBI网站公布的高直链玉米淀粉分支酶基因(Zea mays starch branching enzyme IIb,SBEIIb)序列设计引物,通过PCR反应扩增出常规玉米淀粉分支酶基因的启动子序列,将该扩增片段与T载体连接后测序,并与高直链玉米淀粉分支酶基因启动子的序列进行比较分析。[结果]结果表明:玉米淀粉分支酶基因启动子与公布的启动子序列同源性高达99.3%,序列差异Pi值为0.007 16,该差异主要是SN(P单核苷酸多态性)和Inde(l插入/缺失)造成的,推测该差异可能会影响到淀粉分支酶基因的表达,是造成玉米直链淀粉含量差异的因素之一。[结论]该研究为深入了解玉米直链淀粉合成机理提供了重要依据。

[Objective] the aim of this paper was to study whether there was difference in different starch content promoters and influence on amylose synthesis routes. [Method] Genome DNA of Zea mays was extracted from conventional corn leaf. And primers were designed according to the sequence of corn starch branching enzyme gene with high amylose content published by NCBI. The promoter sequence of conventional maize starch branching enzyme gene was amplified by PCR, which was then recombined with T-vector. [Result] Result showed that there was 99.3% homology between the promoter of corn starch branching enzyme gene and the published promoter. Their difference was mainly caused by single nucleotide polymorphism （SNP） and Indel （insert/delete）, which might impact the expression of starch branching enzyme gene and was the main factor caused the difference of corn amylose content. [Conclusion] The research result offered important evidence in further studying the synthesis mechanism of corn amylose.