玉米糖运载蛋白基因ZmSWEET10a的生物信息和表达分析  

Bioinformatic and Expression Analysis of Sugar Transporter Gene ZmSWEET10a in Maize

作　　者：杨于天程 范会 王姣姣[1] 朱娜[1] 刘征[1] Yang Yutiancheng;Fan Hui;Wang Jiaojiao;Zhu Na;Liu Zheng(College of Life Sciences,Hebei University,Baoding,071002;Whitefield School,St.Louis,63141)

机构地区：[1]河北大学生命科学学院,保定071002 [2]Whitefield School,St.Louis,63141

出　　处：《分子植物育种》2018年第20期6537-6544,共8页Molecular Plant Breeding

基　　金：由河北省自然科学基金(C2015201176)资助

摘　　要：在植物体内,蔗糖转运蛋白(SWEET)在蔗糖转运过程中发挥重要作用。本研究运用一系列生物信息学方法对C4作物玉米ZmSWEET10a基因及其蛋白进行了结构及功能分析。结果分析表明,该蛋白具备跨膜运输蛋白的典型特征。另外,该基因在授粉后18 d表达量达到峰值,暗示着该基因是促进糖运输的关键基因,对于源叶向籽粒库进行糖的输出发挥重要作用。进一步检查ZmSWEET10a基因及糖合成、运输相关基因在玉米叶片花环状结构中的表达量,结果显示蔗糖磷酸转运蛋白基因(ZmSPS)、果糖-1,6-二磷酸酶基因(ZmFBPase)、糖转运蛋白基因ZmSWEET10a、ZmGPT2及ZmSUT等参与蔗糖合成和运输的基因均在维管束鞘细胞中存在特异性高表达。可见,在C4玉米叶片中,不仅卡尔文循环的产物三碳糖在维管束鞘细胞中合成,其光合同化物的运输形式-蔗糖的合成及运出也是在维管束鞘细胞中发生,表明C4玉米维管束鞘细胞中同时存在光合同化物的高效合成与同化物的高效运出机制,构成一个统一的有机体。因此,ZmSWEET10a基因是玉米SWEET基因家族中具有C4特异性的关键糖输出基因。总之,深入探讨ZmSWEET10a基因的特性及其在授粉不同天数的表达变化、以及该基因在维管束鞘细胞的特异性表达,将加深对玉米高光效机制的了解,并为提高作物产量的分子育种提供了新的基因元件。In plants, sucrose transporter SWEET plays a crucial role in the transport of sucrose. In this study, a series of bioinformatics methods were used to analyze the structures and functions of ZmSWEETIOa gene and its protein in C4 crop maize. The results showed that the protein had typical characteristics of transmembrane transport protein. Additionally, the expression of this gene reached the maximum on the 18th day after pollination, suggesting that this gene was the key gene responsible for sugar transport and played an important role in transporting sugar from source leaves to sink seeds. Further inspection on the expressions of ZmSWEETIOa gene and genes related to sucrose synthesis and transport within the Kranz structure of maize leaves indicated that genes involved in the synthesis and transport of sucrose, such as ZmSPS, ZmFBPase, ZmSWEETIOa, ZmGPT2 and ZmSUT, all had high specific expression in vascular bundle sheath cells. From this it could be seen that in C4 maize, not only triose, the end product of Calvin cycle, was synthesized in bundle sheath cells, but also sucrose, the transport form ofphotosynthates, was synthesized in and transported from bundle sheath cells. This suggested that in bundle sheath cells of Ca maize, there existed both high efficient synthesis and high efficient transport of photosynthates. Therefore, ZmSWEET10a was a key sugar transporter gene with C4 specificity in maize SWEET gene family. In all, in-depth exploration of the properties of ZmSWEET10a gene and its protein, the expression patterns of the gene after pollination and the cell-specific expression within the Kranz structure would shed light on revealing the mechanisms of high photosynthetic efficiency in Ca maize and would provide a new gene element for molecular breeding aiming on high crop yield.

关 键 词：玉米 糖运载蛋白基因 生物信息 维管束鞘细胞特异性表达 

分 类 号：S513[农业科学—作物学] Q943.2[生物学—植物学]