异源表达Hvsusiba2基因水稻的淀粉含量及相关酶谱分析  

Utilization of Heterologous Expression of Hvsusiba2 to Increase Grain and Stalk Starch Contents and Amylopectin Synthase Activity in Rice

作　　者：单贞[1] 苏军[1] 陈在杰[1] 胡昌泉[1] 

机构地区：[1]福建省农业遗传工程重点实验室/福建省农业科学院生物技术研究所,福建福州350003

出　　处：《福建农业学报》2017年第3期229-233,共5页Fujian Journal of Agricultural Sciences

基　　金：福建省科技计划项目--省属公益类科研院所基本科研专项(2015N0037);福建省农业科学院科技重大专项(A2015-01)

摘　　要：Hvsusiba2是一个来源于大麦的糖信号转录因子,它作用于淀粉合成途径的上游,是大麦淀粉合成途径的关键调控因子。本研究利用前期研究获得的转Hvsusiba2水稻纯合株系,探讨Hvsusiba2转录因子过表达对水稻淀粉合成的影响,并通过酶谱分析方法分析Hvsusiba2在水稻中的异源表达对支链淀粉合成同工酶的调控作用。结果显示:Hvsusiba2在水稻中的异源表达能够提高籽粒中总淀粉含量,增加淀粉含量达4.33%~9.22%,茎鞘的淀粉含量提高1倍,幼嫩种子发育过程中淀粉累积快速增加期为花后15d起。对该时期的支链淀粉合成酶同工酶分析提示异源表达Hvsusiba2是通过提高籽粒中淀粉分支酶中淀粉分支酶SBEIIb、淀粉分支酶SBEI、异淀粉酶Isoamylase以及淀粉酶Amylase的活性改变水稻的支链淀粉合成,但淀粉分支酶中SBEIIa的活性不受Hvsusiba2转录因子的调控。Hvsusiba2is a transcription factor acting on the upstream of starch synthesis pathway.It is the key starch synthesis regulator in barley.To understand whether the gene has a similar function in rice,a transgenic homozygous rice line with the barley Hvsusiba2 was created previously.The cultivar was used in this study to compare its starch content and amylopectin synthase activity with the wild type.The results showed that the transgenic line exhibited a higher starch contents in the mature grains and stalks,but not in the leaves or roots,than that in the wild type.Starch accumulation dynamics in the process of grain development were similar between the transgene line and the wild counterpart in the initial 12 days after flowering,but markedly increased 15 days after flowering in the transgenic line.It suggested that Hvsusiba2 might not start affecting the starch synthesis until after mid and late grain filling stages in rice.Furthermore,the activities of amylopectin synthases,such as SBEIIb,SBEI,isoamylase and amylase,were enhanced in the developing grains of transgenic line,but the SBEIIa and pullulanase were not affected by Hvsusiba2.It appeared that the heterologous expression of Hvsusiba2 could increase the starch content,and likely,the activities of several amylopectin synthases as well,in rice similar to what it does in barley.

关 键 词：HeuSba2 水稻 总淀粉 支链淀粉合成酶 

分 类 号：S511[农业科学—作物学]