小麦分蘖角度TaTAC1基因同源克隆及表达分析  

Molecular Characterization and Expression Analysis of TaTAC1 gene in Triticum aestivum L.

作　　者：曹鑫[1] 邓梅[1] 张正丽[1] 刘宇娇 杨希兰[1] 周红[1] 刘亚西[1] CAO Xin DENG Mei ZHANG Zheng-li LIU Yu-jiao YANG Xi-lan ZHOU Hong LIU Ya-xi(Laboratory of Molecular Biology, Wheat Research Institute of Sichuan Agricultural University, Chengdu 611130)

机构地区：[1]四川农业大学小麦研究所分子生物学实验室,成都611130

出　　处：《植物遗传资源学报》2017年第1期125-132,共8页Journal of Plant Genetic Resources

基　　金：四川省科技支撑计划(2016NZ0057);国家自然科学基金(31301317)

摘　　要：分蘖角度影响植物群体结构、光合效率以及植株的形态建成,最终影响其产量及品质。小麦中关于分蘖角度的研究鲜有报道。前人研究显示,水稻OsTAC1正向调控分蘖角度的大小,玉米Zm TAC1与叶片角度呈正相关。本研究的目的是解析Ta TAC1的表达模式并初步了解该基因的分子遗传机制及其与分蘖角度的遗传关系。本研究以CN16、SM969、Lan2399、SHW-1为材料,利用同源克隆分离获得Ta TAC1,利用生物信息学软件对Ta TAC1进行序列特征分析,应用实时荧光定量PCR对其表达模式进行分析,并进行Ta TAC1蛋白的亚细胞定位分析。结果显示,Ta TAC1长度约1.1~1.2 kb,包括780 bp的完整开放阅读框和320~370 bp的3'-UTR。Ta TAC1的c DNA序列分为2类,其中CN16-2、SM969-2的第10号碱基发生突变,引起终止子提前,导致Ta TAC1表达受阻;Lan2399-2和SHW-1-2在109~115碱基位置有"CGCGCG"片段插入,导致蛋白质β-折叠片减少。表达分析表明,Ta TAC1在分蘖期的叶鞘、茎高效表达,分蘖节其次,叶与根表达量最低。相关分析表明该基因在分蘖节各时期表达量与分蘖角度呈显著正相关,Pearson相关系数为0.677,其他组织表达量与分蘖角度无显著相关性。亚细胞定位分析显示Ta TAC1定位于细胞膜。从上述结果可以推测Ta TAC1在mRNA水平上正向调控分蘖角度,且可能参与生长素极性运输过程从而改变分蘖角度大小。Tillering angle affects plant population structure, photosynthetic efficiency and morphogenesis. It thus could ultimately affect the yield and quality for a given plant. To our knowledge, the studies on tillering angle in wheat are limited. It was reported that OsTAC1 in rice positively controlled tillering angle and ZmTAC1 in maize was positively correlated with blade angle. Here, we are aiming at analyzing expression pattern of TaTAC1 and revealing the molecular genetic mechanisms of this gene and its genetic relationship with the tillering angle. To this end, we used four genotypes of common wheat, CN16, SM969, Lan2399 and SHW-1 for isolating TaTAC1 based on homology cloning, characterized its sequence, analyzed its expression pattern using real-time fluorescent quantitative PCR, and performed the subcellular localization of this gene. Our results showed that TaTAC1 was about 1.1-1.2 kb in length including 780 bp of a complete opening reading frame （ORF） and 320-370 bp of 3＇-UTR. Two types of cDNA sequences for TaTAC1 were identified. The sequences of CN16-2 and SM969-2 were grouped in Type I. The 10th base for these sequences was mutated, leading to the presence of a terminator. Expression of these genes was thus not detected. The sequences of Lan2399-2 and SHW-1-2 were grouped in Type II. A fragment of＂ CGCGCG＂ was inserted between 109th and 115th of these sequences,leading to the reduction of beta-pleated sheets. Expression profiling indicated that TaTAC1 was mostly expressed in leaf sheath and stem at tillering stage followed by tillering node and least in leaf and root. Correlation analysis showed that the expression abundance of TaTAC1 in tillering node throughout the investigated stages was significantly positively correlated with the angles of tillering （R = 0. 677）. No significant correlation was detected between expression of TaTAC1 in other tissues and tillering angle. TaTAC1 was located in cell membrane. Taken together, we suggested that TaTAC1 positively regulated tillering angle at

关 键 词：小麦(Triticum AESTIVUM L.) 分蘖角度 TaTAC1 同源克隆 表达分析 

分 类 号：S512.1[农业科学—作物学]