不同类型玉米籽粒淀粉积累、相关酶活及基因表达差异分析  

ANALYSIS OF STARCH ACCUMULATION,CORRESPONDING ENZYME ACTIVITY AND GENE EXPRESSION AMONG DIFFERENT TYPES OF CORNS

作　　者：陈江[1,2] 王燕[1,2] 黄斌全[1,2] 胡玉峰[1,2] 刘应红[1,2] 顾勇[1,2] 李炀平[1,2] 张军杰[3] 刘汉梅[3] 黄玉碧[1,4,2] 

机构地区：[1]四川农业大学玉米研究所,四川雅安625014 [2]农业部西南玉米生物学与遗传育种重点实验室,四川成都611130 [3]四川农业大学生命理学院,四川雅安625014 [4]西南作物基因资源与遗传改良教育部重点实验室,四川雅安625014

出　　处：《核农学报》2012年第2期217-230,共14页Journal of Nuclear Agricultural Sciences

基　　金：国家"973"计划项目(2011CB100100)

摘　　要：为探究不同类型玉米淀粉形成机理,对普通玉米、甜玉米、糯玉米淀粉积累、相关酶活及基因表达进行测定,分析不同类型玉米淀粉积累、相关酶活及基因表达之间的差异及相互关系。结果表明,不同类型玉米总淀粉和直链淀粉百分含量为:普通玉米>糯玉米>甜玉米,支链淀粉百分含量为:糯玉米>普通玉米>甜玉米,灌浆期间总淀粉和直链淀粉含量3个玉米类型间差异显著;灌浆期间,普通玉米各淀粉合成相关酶活性最高,甜玉米淀粉合成相关酶活性最低,糯玉米则介于普通玉米和甜玉米之间,但其GBSS酶活性很小。灌浆期间3个类型玉米除GBSS酶活性差异不显著外,其他淀粉合成相关酶活性差异显著;普通玉米淀粉合成相关基因表达量总体均高于甜玉米和糯玉米,甜玉米和糯玉米相关突变基因仍存在表达。表明不同类型玉米淀粉含量和组成上差异明显;普通玉米淀粉的形成需要淀粉合成相关酶相互作用,淀粉合成相关酶活性的缺失会改变淀粉组成;不同类型玉米淀粉合成相关基因表达差异显著,但都存在转录活性。对普通玉米进行相关性分析同时发现,淀粉的合成不仅受到转录调控,还受到转录后调控,淀粉的合成是淀粉合成各酶之间相互协调的结果。The starch accumulation, the starch biosynthetic enzymes activity and gene expression of different types of maize were measured, and the differences and relations between them were analyzed in order to further understand the starch synthesis in different maize types and improve the quality of maize starch. The results showed that the percentage composition of total starch and amylose were in the order of normal corn 〉 waxy corn 〉 sweet corn, and the amylopectin was waxy corn 〉 normal corn 〉 sweet corn. Total starch and amylose were significantly （ P 〈 O. O1 and P 〈 O. 05, respectively） different among different types of corns. During the filling period, the enzymes involved in starch synthesiswere highest in normal corn, lowest in sweet corn. Compared to the waxy corn, though the GBSS activities in waxy corn was significantly low during the grain filling period . The starch synthesis enzymes except the GBSS were significantly different among the three types of corn. The expression levels of starch genes in normal corn were higher than those in other two kinds of corn. However there are still transcriptions in the mutants sh2 and wax with other two kinds of corn, indicating that there are differences in starch synthesis among different mutants. The synthesis of normal starch is orchestrated by the enzymes involved in starch synthesis and the deficiency of any one enzyme in starch synthesis will change the starch constitution. In addition, the gene expression levels were found to be different among normal corn, sweet corn and waxy corn,and the mutant gene has the transcriptional activity. The correlation analysis of normal corn among starch accumulations, enzymes activities and the gene expressions showed that both transcription and posttranscription regulate the starch metabolism. Therefore the starch synthesis is the result of the synergistic effect of each starch synthesis enzyme.

关 键 词：玉米 淀粉合成 淀粉 酶活 基因表达 差异 

分 类 号：S513[农业科学—作物学]