过表达ZmbHLH167基因正向调控玉米籽粒的淀粉合成  

Overexpression of maize ZmbHLH167 positively regulates starch synthesis in maize

作　　者：舒建国 陈逸蓉 陈龙 武健东 SHU Jianguo;CHEN Yirong;CHEN Long;WU Jiandong(School of Life Sciences,Anhui Agricultural University,Hefei 230036;National Engineering Laboratory of Crop Stress Resistance Breeding and Disaster Reduction,Hefei 230036)

机构地区：[1]安徽农业大学生命科学学院,合肥230036 [2]作物抗逆育种与减灾国家地方联合工程实验室,合肥230036

出　　处：《安徽农业大学学报》2024年第6期907-913,共7页Journal of Anhui Agricultural University

基　　金：国家自然科学基金(32372019)资助。

摘　　要：旨在从玉米中克隆调控淀粉合成的相关基因ZmbHLH167,分析其分子特征并研究其调控玉米籽粒淀粉合成的生物学功能。以玉米KN5585为供试材料,克隆ZmbHLH167全长序列并通过对ZmbHLH167的组织表达、亚细胞定位和酵母转录活性等特征分析、结合ZmbHLH167基因过表达玉米植株籽粒形态、籽粒成分分析,明确ZmbHLH167在籽粒发育和淀粉合成中的功能。通过实时荧光定量PCR,对淀粉合成相关酶基因进行定量分析,分析ZmbHLH167调控籽粒淀粉合成相关基因的表达情况。结果表明:荧光定量PCR显示ZmbHLH167基因在胚乳和叶片中表达量较高;亚细胞定位结果显示ZmbHLH167是一个核定位蛋白;转录自激活活性检测表明,ZmbHLH167在酵母中并不具备转录自激活活性;酵母双杂交结果表明ZmbHLH167以同源二聚体形式发挥作用。农艺性状分析和籽粒组成成分分析结果表明ZmbHLH167能够正向调控玉米籽粒的长、宽、百粒重以及籽粒中淀粉含量,对籽粒中可溶性糖和还原性糖的变化有负向调节作用。实时荧光定量PCR结果显示,过表达籽粒的ZmGBSSI、ZmGBSSIIa、ZmGBSSIIb、ZmISAI、ZmISAII和ZmISAIII淀粉合成相关酶基因表达量在授粉后15d显著高于野生型,表明ZmbHLH167能够正向调节籽粒淀粉合成相关基因的表达。研究表明转录因子ZmbHLH167对提高玉米籽粒淀粉含量具有重要作用。The aim of this study was to clone ZmbHLH167,a gene related to the regulation of starch synthesis from maize,and analyze its molecular characteristics and investigate its biological function in regulating starch syn-thesis in maize kernels.The full-length sequence of ZmbHLH167 was cloned from maize KN5585,the tissue expres-sion,subcellular localization and yeast transcriptional activity of ZmbHLH167 were characterized,and the morphol-ogy and the composition of kernels in maize overexpressing ZmbHLH167 gene for clarifying the functions of ZmbHLH167 in starch synthesis were analyzed.The expression levels of gene related to starch synthesis in kernels were analyzed by quantitative real-time PCR.As results,quantitative PCR assay revealed that ZmbHLH167 gene was highly expressed in the endosperm and leaves;subcellular localization results showed that ZmbHLH167 was a nuclear localized protein;transcriptional activity assay showed that ZmbHLH167 did not possess transcriptional ac-tivation activity in yeast;yeast two-hybrid results indicated that ZmbHLH167 functioned as a homodimer.Analysis of agronomic traits and kernel composition showed that ZmbHLH167 positively regulated the length,width,and 100-kernel weight of the maize kernels,as well as the contents of various starches in the kernels,and negatively reg-ulated the changes of soluble and reducing sugars in the kernels.Real-time quantitative PCR results showed that the expression levels of ZmGBSSI,ZmGBSSIIa,ZmGBSSIIb,ZmISAI,ZmISAII and ZmISAIII at 15 days after pollination in transgenic lines were higher than those of the wild type.These results indicated that ZmbHLH167 positively regu-lates the expression of starch synthesis-related genes in seeds.In conclusion,this study demonstrated that the tran-scription factor ZmbHLH167 has an important role in increasing the starch content of maize kernels.

关 键 词：玉米 淀粉合成 转录调控 ZmbHLH167 胚乳 

分 类 号：S513[农业科学—作物学]