木薯淀粉分支酶基因MeSBE2.2的克隆和表达分析  

Cloning and expression analysis of starch branching enzyme gene(MeSBE2.2)in cassava

作　　者：裴金利[1] 陈新[2] 夏志强[2] 刘陈[2] 马平安[2] 张圣奎 王文泉[2] 

机构地区：[1]海南大学农学院,海口570228 [2]中国热带农业科学院热带生物技术研究所,海口571101

出　　处：《中国农业大学学报》2015年第4期36-41,共6页Journal of China Agricultural University

基　　金：国家"973计划"项目(2010CB126601);国家木薯产业技术体系项目(CARS-12);国家国际科技合作计划项目(2011DFB31690)

摘　　要：为了明确淀粉分支酶(SBE)在木薯淀粉合成中的功能,利用RT-PCR方法克隆得到了MeSBE2.2序列,并通过实时定量PCR(Q-PCR)分析其转录特点。结果表明,MeSBE2.2全长2 053bp,编码616个氨基酸,其编码蛋白质序列与蓖麻SBEII氨基酸序列的同源性最高,为91%。研究其转录特点发现:MeSBE2.2在块根和叶片中的表达模式有品种间差异性;器官特异性表达分析结果表明,MeSBE2.2主要在木薯块根中柱中表达;于3个不同生长时期的表达分析发现,MeSBE2.2在块根中表达平稳,在叶片中其表达量随植株生长呈显著下降趋势。本研究结果为进一步研究SBE家族在木薯块根淀粉合成中的功能提供了重要依据。To investigate the function of starch branching enzyme（SBE）in starch biosynthesis in cassava,one gene encoding starch branching enzyme,named MeSBE2.2 was cloned by RT-PCR and its expression patterns were studied by real-time quantitative PCR（Q-PCR）.The results showed that the 2 053 bp full-length sequence encoded 616 amino acids and the deduced protein sequence shared the highest similarity of 91% with Ricinus communis SBEII protein sequence.Expression analysis results showed that MeSBE2.2 was differentially expressed in roots and leaves in various cultivars.Organ-specific expression analysis revealed that MeSBE2.2 was mainly expressed in stele.The expression level of MeSBE2.2 in roots at three different growth stages remained stable while it was significantly decreased in leaves as the plant aged.This study paves a way for further understanding the function of SBE gene family in starch metabolism in cassava.

关 键 词：木薯(Manihot esculenta Crantz) 淀粉分支酶 克隆 表达分析 

分 类 号：S533[农业科学—作物学]